diff --git a/lib/nghttp2_session.c b/lib/nghttp2_session.c
index e17995a0..2c25e903 100644
--- a/lib/nghttp2_session.c
+++ b/lib/nghttp2_session.c
@@ -512,7 +512,7 @@ static int free_streams(nghttp2_map_entry *entry, void *ptr) {
   session = (nghttp2_session *)ptr;
   mem = &session->mem;
   stream = (nghttp2_stream *)entry;
-  item = stream->data_item;
+  item = stream->item;
 
   if (item && !item->queued && item != session->aob.item) {
     nghttp2_outbound_item_free(item, mem);
@@ -549,7 +549,7 @@ void nghttp2_session_del(nghttp2_session *session) {
   nghttp2_stream_roots_free(&session->roots);
 
   /* Have to free streams first, so that we can check
-     stream->data_item->queued */
+     stream->item->queued */
   nghttp2_map_each_free(&session->streams, free_streams, session);
   nghttp2_map_free(&session->streams);
 
@@ -733,7 +733,7 @@ int nghttp2_session_add_item(nghttp2_session *session,
         item->weight = stream->effective_weight;
         item->cycle = session->last_cycle;
 
-        rv = nghttp2_stream_attach_data(stream, item, session);
+        rv = nghttp2_stream_attach_item(stream, item, session);
 
         if (rv != 0) {
           return rv;
@@ -764,14 +764,14 @@ int nghttp2_session_add_item(nghttp2_session *session,
     return NGHTTP2_ERR_STREAM_CLOSED;
   }
 
-  if (stream->data_item) {
+  if (stream->item) {
     return NGHTTP2_ERR_DATA_EXIST;
   }
 
   item->weight = stream->effective_weight;
   item->cycle = session->last_cycle;
 
-  rv = nghttp2_stream_attach_data(stream, item, session);
+  rv = nghttp2_stream_attach_item(stream, item, session);
 
   if (rv != 0) {
     return rv;
@@ -979,12 +979,12 @@ int nghttp2_session_close_stream(nghttp2_session *session, int32_t stream_id,
   DEBUGF(fprintf(stderr, "stream: stream(%p)=%d close\n", stream,
                  stream->stream_id));
 
-  if (stream->data_item) {
+  if (stream->item) {
     nghttp2_outbound_item *item;
 
-    item = stream->data_item;
+    item = stream->item;
 
-    rv = nghttp2_stream_detach_data(stream, session);
+    rv = nghttp2_stream_detach_item(stream, session);
 
     if (rv != 0) {
       return rv;
@@ -1709,10 +1709,10 @@ static int session_prep_frame(nghttp2_session *session,
           rv = session_predicate_headers_send(session, stream);
 
           if (rv != 0) {
-            if (stream && stream->data_item == item) {
+            if (stream && stream->item == item) {
               int rv2;
 
-              rv2 = nghttp2_stream_detach_data(stream, session);
+              rv2 = nghttp2_stream_detach_item(stream, session);
 
               if (nghttp2_is_fatal(rv2)) {
                 return rv2;
@@ -1880,7 +1880,7 @@ static int session_prep_frame(nghttp2_session *session,
     stream = nghttp2_session_get_stream(session, frame->hd.stream_id);
 
     if (stream) {
-      assert(stream->data_item == item);
+      assert(stream->item == item);
     }
 
     rv = nghttp2_session_predicate_data_send(session, stream);
@@ -1888,7 +1888,7 @@ static int session_prep_frame(nghttp2_session *session,
       if (stream) {
         int rv2;
 
-        rv2 = nghttp2_stream_detach_data(stream, session);
+        rv2 = nghttp2_stream_detach_item(stream, session);
 
         if (nghttp2_is_fatal(rv2)) {
           return rv2;
@@ -1907,7 +1907,7 @@ static int session_prep_frame(nghttp2_session *session,
          queue when session->remote_window_size > 0 */
       assert(session->remote_window_size > 0);
 
-      rv = nghttp2_stream_defer_data(
+      rv = nghttp2_stream_defer_item(
           stream, NGHTTP2_STREAM_FLAG_DEFERRED_FLOW_CONTROL, session);
 
       if (nghttp2_is_fatal(rv)) {
@@ -1923,7 +1923,7 @@ static int session_prep_frame(nghttp2_session *session,
         nghttp2_session_pack_data(session, &session->aob.framebufs,
                                   next_readmax, frame, &item->aux_data.data);
     if (framerv == NGHTTP2_ERR_DEFERRED) {
-      rv = nghttp2_stream_defer_data(stream, NGHTTP2_STREAM_FLAG_DEFERRED_USER,
+      rv = nghttp2_stream_defer_item(stream, NGHTTP2_STREAM_FLAG_DEFERRED_USER,
                                      session);
 
       if (nghttp2_is_fatal(rv)) {
@@ -1935,7 +1935,7 @@ static int session_prep_frame(nghttp2_session *session,
       return NGHTTP2_ERR_DEFERRED;
     }
     if (framerv == NGHTTP2_ERR_TEMPORAL_CALLBACK_FAILURE) {
-      rv = nghttp2_stream_detach_data(stream, session);
+      rv = nghttp2_stream_detach_item(stream, session);
 
       if (nghttp2_is_fatal(rv)) {
         return rv;
@@ -1949,7 +1949,7 @@ static int session_prep_frame(nghttp2_session *session,
       return framerv;
     }
     if (framerv < 0) {
-      rv = nghttp2_stream_detach_data(stream, session);
+      rv = nghttp2_stream_detach_item(stream, session);
 
       if (nghttp2_is_fatal(rv)) {
         return rv;
@@ -2248,8 +2248,8 @@ static int session_after_frame_sent1(nghttp2_session *session) {
         break;
       }
 
-      if (stream->data_item == item) {
-        rv = nghttp2_stream_detach_data(stream, session);
+      if (stream->item == item) {
+        rv = nghttp2_stream_detach_item(stream, session);
 
         if (nghttp2_is_fatal(rv)) {
           return rv;
@@ -2377,14 +2377,14 @@ static int session_after_frame_sent1(nghttp2_session *session) {
     }
 
     if (stream && aux_data->eof) {
-      rv = nghttp2_stream_detach_data(stream, session);
+      rv = nghttp2_stream_detach_item(stream, session);
 
       if (nghttp2_is_fatal(rv)) {
         return rv;
       }
 
       /* Call on_frame_send_callback after
-         nghttp2_stream_detach_data(), so that application can issue
+         nghttp2_stream_detach_item(), so that application can issue
          nghttp2_submit_data() in the callback. */
       if (session->callbacks.on_frame_send_callback) {
         rv = session_call_on_frame_send(session, frame);
@@ -2493,7 +2493,7 @@ static int session_after_frame_sent2(nghttp2_session *session) {
        further data. */
     if (nghttp2_session_predicate_data_send(session, stream) != 0) {
       if (stream) {
-        rv = nghttp2_stream_detach_data(stream, session);
+        rv = nghttp2_stream_detach_item(stream, session);
 
         if (nghttp2_is_fatal(rv)) {
           return rv;
@@ -2537,7 +2537,7 @@ static int session_after_frame_sent2(nghttp2_session *session) {
 
           aob->item->queued = 1;
         } else {
-          rv = nghttp2_stream_defer_data(
+          rv = nghttp2_stream_defer_item(
               stream, NGHTTP2_STREAM_FLAG_DEFERRED_FLOW_CONTROL, session);
 
           if (nghttp2_is_fatal(rv)) {
@@ -2559,7 +2559,7 @@ static int session_after_frame_sent2(nghttp2_session *session) {
         return rv;
       }
       if (rv == NGHTTP2_ERR_DEFERRED) {
-        rv = nghttp2_stream_defer_data(
+        rv = nghttp2_stream_defer_item(
             stream, NGHTTP2_STREAM_FLAG_DEFERRED_USER, session);
 
         if (nghttp2_is_fatal(rv)) {
@@ -2582,7 +2582,7 @@ static int session_after_frame_sent2(nghttp2_session *session) {
           return rv;
         }
 
-        rv = nghttp2_stream_detach_data(stream, session);
+        rv = nghttp2_stream_detach_item(stream, session);
 
         if (nghttp2_is_fatal(rv)) {
           return rv;
@@ -2647,7 +2647,7 @@ static ssize_t nghttp2_session_mem_send_internal(nghttp2_session *session,
         frame = &item->frame;
         stream = nghttp2_session_get_stream(session, frame->hd.stream_id);
 
-        if (stream && item == stream->data_item &&
+        if (stream && item == stream->item &&
             stream->dpri != NGHTTP2_STREAM_DPRI_TOP) {
           /* We have DATA with higher priority in queue within the
              same dependency tree. */
@@ -3531,7 +3531,7 @@ static int update_remote_initial_window_size_func(nghttp2_map_entry *entry,
   if (stream->remote_window_size > 0 &&
       nghttp2_stream_check_deferred_by_flow_control(stream)) {
 
-    rv = nghttp2_stream_resume_deferred_data(
+    rv = nghttp2_stream_resume_deferred_item(
         stream, NGHTTP2_STREAM_FLAG_DEFERRED_FLOW_CONTROL, arg->session);
 
     if (nghttp2_is_fatal(rv)) {
@@ -4111,7 +4111,7 @@ static int session_on_stream_window_update_received(nghttp2_session *session,
   if (stream->remote_window_size > 0 &&
       nghttp2_stream_check_deferred_by_flow_control(stream)) {
 
-    rv = nghttp2_stream_resume_deferred_data(
+    rv = nghttp2_stream_resume_deferred_item(
         stream, NGHTTP2_STREAM_FLAG_DEFERRED_FLOW_CONTROL, session);
 
     if (nghttp2_is_fatal(rv)) {
@@ -6038,11 +6038,11 @@ int nghttp2_session_resume_data(nghttp2_session *session, int32_t stream_id) {
   int rv;
   nghttp2_stream *stream;
   stream = nghttp2_session_get_stream(session, stream_id);
-  if (stream == NULL || !nghttp2_stream_check_deferred_data(stream)) {
+  if (stream == NULL || !nghttp2_stream_check_deferred_item(stream)) {
     return NGHTTP2_ERR_INVALID_ARGUMENT;
   }
 
-  rv = nghttp2_stream_resume_deferred_data(
+  rv = nghttp2_stream_resume_deferred_item(
       stream, NGHTTP2_STREAM_FLAG_DEFERRED_USER, session);
 
   if (nghttp2_is_fatal(rv)) {
diff --git a/lib/nghttp2_stream.c b/lib/nghttp2_stream.c
index bdab95b5..8d5fec61 100644
--- a/lib/nghttp2_stream.c
+++ b/lib/nghttp2_stream.c
@@ -42,7 +42,7 @@ void nghttp2_stream_init(nghttp2_stream *stream, int32_t stream_id,
   stream->state = initial_state;
   stream->shut_flags = NGHTTP2_SHUT_NONE;
   stream->stream_user_data = stream_user_data;
-  stream->data_item = NULL;
+  stream->item = NULL;
   stream->remote_window_size = remote_initial_window_size;
   stream->local_window_size = local_initial_window_size;
   stream->recv_window_size = 0;
@@ -57,7 +57,7 @@ void nghttp2_stream_init(nghttp2_stream *stream, int32_t stream_id,
   stream->closed_prev = NULL;
   stream->closed_next = NULL;
 
-  stream->dpri = NGHTTP2_STREAM_DPRI_NO_DATA;
+  stream->dpri = NGHTTP2_STREAM_DPRI_NO_ITEM;
   stream->num_substreams = 1;
   stream->weight = weight;
   stream->effective_weight = stream->weight;
@@ -71,7 +71,7 @@ void nghttp2_stream_init(nghttp2_stream *stream, int32_t stream_id,
 }
 
 void nghttp2_stream_free(nghttp2_stream *stream _U_) {
-  /* We don't free stream->data_item.  If it is assigned to aob, then
+  /* We don't free stream->item.  If it is assigned to aob, then
      active_outbound_item_reset() will delete it.  If it is queued,
      then it is deleted when pq is deleted in nghttp2_session_del().
      Otherwise, nghttp2_session_del() will delete it. */
@@ -81,14 +81,14 @@ void nghttp2_stream_shutdown(nghttp2_stream *stream, nghttp2_shut_flag flag) {
   stream->shut_flags |= flag;
 }
 
-static int stream_push_data(nghttp2_stream *stream, nghttp2_session *session) {
+static int stream_push_item(nghttp2_stream *stream, nghttp2_session *session) {
   int rv;
   nghttp2_outbound_item *item;
 
-  assert(stream->data_item);
-  assert(stream->data_item->queued == 0);
+  assert(stream->item);
+  assert(stream->item->queued == 0);
 
-  item = stream->data_item;
+  item = stream->item;
 
   /* If item is now sent, don't push it to the queue.  Otherwise, we
      may push same item twice. */
@@ -200,7 +200,7 @@ static void stream_update_dep_effective_weight(nghttp2_stream *stream) {
 
   /* stream->sum_norest_weight == 0 means there is no
      NGHTTP2_STREAM_DPRI_TOP under stream */
-  if (stream->dpri != NGHTTP2_STREAM_DPRI_NO_DATA ||
+  if (stream->dpri != NGHTTP2_STREAM_DPRI_NO_ITEM ||
       stream->sum_norest_weight == 0) {
     return;
   }
@@ -235,8 +235,8 @@ static void stream_update_dep_effective_weight(nghttp2_stream *stream) {
       continue;
     }
 
-    if (si->dpri == NGHTTP2_STREAM_DPRI_NO_DATA) {
-      DEBUGF(fprintf(stderr, "stream: stream=%d no_data, ignored\n",
+    if (si->dpri == NGHTTP2_STREAM_DPRI_NO_ITEM) {
+      DEBUGF(fprintf(stderr, "stream: stream=%d no_item, ignored\n",
                      si->stream_id));
 
       /* Since we marked NGHTTP2_STREAM_DPRI_TOP under si, we make
@@ -285,7 +285,7 @@ static void stream_update_dep_set_top(nghttp2_stream *stream) {
 
   if (stream->dpri == NGHTTP2_STREAM_DPRI_REST) {
     DEBUGF(
-        fprintf(stderr, "stream: stream=%d data is top\n", stream->stream_id));
+        fprintf(stderr, "stream: stream=%d item is top\n", stream->stream_id));
 
     stream->dpri = NGHTTP2_STREAM_DPRI_TOP;
 
@@ -317,9 +317,9 @@ static int stream_update_dep_queue_top(nghttp2_stream *stream,
   }
 
   if (stream->dpri == NGHTTP2_STREAM_DPRI_TOP) {
-    if (!stream->data_item->queued) {
+    if (!stream->item->queued) {
       DEBUGF(fprintf(stderr, "stream: stream=%d enqueue\n", stream->stream_id));
-      rv = stream_push_data(stream, session);
+      rv = stream_push_item(stream, session);
 
       if (rv != 0) {
         return rv;
@@ -343,7 +343,7 @@ static int stream_update_dep_queue_top(nghttp2_stream *stream,
 /*
  * Updates stream->sum_norest_weight and stream->sum_top_weight
  * recursively.  We have to gather effective sum of weight of
- * descendants.  If stream->dpri == NGHTTP2_STREAM_DPRI_NO_DATA, we
+ * descendants.  If stream->dpri == NGHTTP2_STREAM_DPRI_NO_ITEM, we
  * have to go deeper and check that any of its descendants has dpri
  * value of NGHTTP2_STREAM_DPRI_TOP.  If so, we have to add weight of
  * its direct descendants to stream->sum_norest_weight.  To make this
@@ -386,7 +386,7 @@ static int stream_update_dep_sum_norest_weight(nghttp2_stream *stream) {
   return rv;
 }
 
-static int stream_update_dep_on_attach_data(nghttp2_stream *stream,
+static int stream_update_dep_on_attach_item(nghttp2_stream *stream,
                                             nghttp2_session *session) {
   nghttp2_stream *root_stream;
 
@@ -406,11 +406,11 @@ static int stream_update_dep_on_attach_data(nghttp2_stream *stream,
   return stream_update_dep_queue_top(root_stream, session);
 }
 
-static int stream_update_dep_on_detach_data(nghttp2_stream *stream,
+static int stream_update_dep_on_detach_item(nghttp2_stream *stream,
                                             nghttp2_session *session) {
   nghttp2_stream *root_stream;
 
-  stream->dpri = NGHTTP2_STREAM_DPRI_NO_DATA;
+  stream->dpri = NGHTTP2_STREAM_DPRI_NO_ITEM;
 
   root_stream = nghttp2_stream_get_dep_root(stream);
 
@@ -422,49 +422,49 @@ static int stream_update_dep_on_detach_data(nghttp2_stream *stream,
   return stream_update_dep_queue_top(root_stream, session);
 }
 
-int nghttp2_stream_attach_data(nghttp2_stream *stream,
-                               nghttp2_outbound_item *data_item,
+int nghttp2_stream_attach_item(nghttp2_stream *stream,
+                               nghttp2_outbound_item *item,
                                nghttp2_session *session) {
   assert((stream->flags & NGHTTP2_STREAM_FLAG_DEFERRED_ALL) == 0);
-  assert(stream->data_item == NULL);
+  assert(stream->item == NULL);
 
-  DEBUGF(fprintf(stderr, "stream: stream=%d attach data=%p\n",
-                 stream->stream_id, data_item));
+  DEBUGF(fprintf(stderr, "stream: stream=%d attach item=%p\n",
+                 stream->stream_id, item));
 
-  stream->data_item = data_item;
+  stream->item = item;
 
-  return stream_update_dep_on_attach_data(stream, session);
+  return stream_update_dep_on_attach_item(stream, session);
 }
 
-int nghttp2_stream_detach_data(nghttp2_stream *stream,
+int nghttp2_stream_detach_item(nghttp2_stream *stream,
                                nghttp2_session *session) {
-  DEBUGF(fprintf(stderr, "stream: stream=%d detach data=%p\n",
-                 stream->stream_id, stream->data_item));
+  DEBUGF(fprintf(stderr, "stream: stream=%d detach item=%p\n",
+                 stream->stream_id, stream->item));
 
-  stream->data_item = NULL;
+  stream->item = NULL;
   stream->flags &= ~NGHTTP2_STREAM_FLAG_DEFERRED_ALL;
 
-  return stream_update_dep_on_detach_data(stream, session);
+  return stream_update_dep_on_detach_item(stream, session);
 }
 
-int nghttp2_stream_defer_data(nghttp2_stream *stream, uint8_t flags,
+int nghttp2_stream_defer_item(nghttp2_stream *stream, uint8_t flags,
                               nghttp2_session *session) {
-  assert(stream->data_item);
+  assert(stream->item);
 
-  DEBUGF(fprintf(stderr, "stream: stream=%d defer data=%p cause=%02x\n",
-                 stream->stream_id, stream->data_item, flags));
+  DEBUGF(fprintf(stderr, "stream: stream=%d defer item=%p cause=%02x\n",
+                 stream->stream_id, stream->item, flags));
 
   stream->flags |= flags;
 
-  return stream_update_dep_on_detach_data(stream, session);
+  return stream_update_dep_on_detach_item(stream, session);
 }
 
-int nghttp2_stream_resume_deferred_data(nghttp2_stream *stream, uint8_t flags,
+int nghttp2_stream_resume_deferred_item(nghttp2_stream *stream, uint8_t flags,
                                         nghttp2_session *session) {
-  assert(stream->data_item);
+  assert(stream->item);
 
-  DEBUGF(fprintf(stderr, "stream: stream=%d resume data=%p flags=%02x\n",
-                 stream->stream_id, stream->data_item, flags));
+  DEBUGF(fprintf(stderr, "stream: stream=%d resume item=%p flags=%02x\n",
+                 stream->stream_id, stream->item, flags));
 
   stream->flags &= ~flags;
 
@@ -472,16 +472,15 @@ int nghttp2_stream_resume_deferred_data(nghttp2_stream *stream, uint8_t flags,
     return 0;
   }
 
-  return stream_update_dep_on_attach_data(stream, session);
+  return stream_update_dep_on_attach_item(stream, session);
 }
 
-int nghttp2_stream_check_deferred_data(nghttp2_stream *stream) {
-  return stream->data_item &&
-         (stream->flags & NGHTTP2_STREAM_FLAG_DEFERRED_ALL);
+int nghttp2_stream_check_deferred_item(nghttp2_stream *stream) {
+  return stream->item && (stream->flags & NGHTTP2_STREAM_FLAG_DEFERRED_ALL);
 }
 
 int nghttp2_stream_check_deferred_by_flow_control(nghttp2_stream *stream) {
-  return stream->data_item &&
+  return stream->item &&
          (stream->flags & NGHTTP2_STREAM_FLAG_DEFERRED_FLOW_CONTROL);
 }
 
@@ -560,7 +559,7 @@ void nghttp2_stream_dep_insert(nghttp2_stream *dep_stream,
   nghttp2_stream *si;
   nghttp2_stream *root_stream;
 
-  assert(stream->data_item == NULL);
+  assert(stream->item == NULL);
 
   DEBUGF(fprintf(stderr,
                  "stream: dep_insert dep_stream(%p)=%d, stream(%p)=%d\n",
@@ -690,7 +689,7 @@ void nghttp2_stream_dep_add(nghttp2_stream *dep_stream,
                             nghttp2_stream *stream) {
   nghttp2_stream *root_stream;
 
-  assert(stream->data_item == NULL);
+  assert(stream->item == NULL);
 
   DEBUGF(fprintf(stderr, "stream: dep_add dep_stream(%p)=%d, stream(%p)=%d\n",
                  dep_stream, dep_stream->stream_id, stream, stream->stream_id));
diff --git a/lib/nghttp2_stream.h b/lib/nghttp2_stream.h
index 792eb349..50e60a2c 100644
--- a/lib/nghttp2_stream.h
+++ b/lib/nghttp2_stream.h
@@ -100,7 +100,7 @@ typedef enum {
 
 typedef enum {
   NGHTTP2_STREAM_DPRI_NONE = 0,
-  NGHTTP2_STREAM_DPRI_NO_DATA = 0x01,
+  NGHTTP2_STREAM_DPRI_NO_ITEM = 0x01,
   NGHTTP2_STREAM_DPRI_TOP = 0x02,
   NGHTTP2_STREAM_DPRI_REST = 0x04
 } nghttp2_stream_dpri;
@@ -139,7 +139,7 @@ struct nghttp2_stream {
   /* The arbitrary data provided by user for this stream. */
   void *stream_user_data;
   /* Item to send */
-  nghttp2_outbound_item *data_item;
+  nghttp2_outbound_item *item;
   /* stream ID */
   int32_t stream_id;
   /* categorized priority of this stream.  Only stream bearing
@@ -201,9 +201,9 @@ void nghttp2_stream_free(nghttp2_stream *stream);
 void nghttp2_stream_shutdown(nghttp2_stream *stream, nghttp2_shut_flag flag);
 
 /*
- * Defer |stream->data_item|.  We won't call this function in the
- * situation where |stream->data_item| == NULL.  If |flags| is bitwise
- * OR of zero or more of NGHTTP2_STREAM_FLAG_DEFERRED_USER and
+ * Defer |stream->item|.  We won't call this function in the situation
+ * where |stream->item| == NULL.  The |flags| is bitwise OR of zero or
+ * more of NGHTTP2_STREAM_FLAG_DEFERRED_USER and
  * NGHTTP2_STREAM_FLAG_DEFERRED_FLOW_CONTROL.  The |flags| indicates
  * the reason of this action.
  *
@@ -213,7 +213,7 @@ void nghttp2_stream_shutdown(nghttp2_stream *stream, nghttp2_shut_flag flag);
  * NGHTTP2_ERR_NOMEM
  *     Out of memory
  */
-int nghttp2_stream_defer_data(nghttp2_stream *stream, uint8_t flags,
+int nghttp2_stream_defer_item(nghttp2_stream *stream, uint8_t flags,
                               nghttp2_session *session);
 
 /*
@@ -224,16 +224,16 @@ int nghttp2_stream_defer_data(nghttp2_stream *stream, uint8_t flags,
  * cleared if they are set.  So even if this function is called, if
  * one of flag is still set, data does not become active.
  */
-int nghttp2_stream_resume_deferred_data(nghttp2_stream *stream, uint8_t flags,
+int nghttp2_stream_resume_deferred_item(nghttp2_stream *stream, uint8_t flags,
                                         nghttp2_session *session);
 
 /*
- * Returns nonzero if data item is deferred by whatever reason.
+ * Returns nonzero if item is deferred by whatever reason.
  */
-int nghttp2_stream_check_deferred_data(nghttp2_stream *stream);
+int nghttp2_stream_check_deferred_item(nghttp2_stream *stream);
 
 /*
- * Returns nonzero if data item is deferred by flow control.
+ * Returns nonzero if item is deferred by flow control.
  */
 int nghttp2_stream_check_deferred_by_flow_control(nghttp2_stream *stream);
 
@@ -322,7 +322,7 @@ void nghttp2_stream_dep_add(nghttp2_stream *dep_stream, nghttp2_stream *stream);
 void nghttp2_stream_dep_remove(nghttp2_stream *stream);
 
 /*
- * Attaches |data_item| to |stream|.  Updates dpri members in this
+ * Attaches |item| to |stream|.  Updates dpri members in this
  * dependency tree.
  *
  * This function returns 0 if it succeeds, or one of the following
@@ -331,14 +331,14 @@ void nghttp2_stream_dep_remove(nghttp2_stream *stream);
  * NGHTTP2_ERR_NOMEM
  *     Out of memory
  */
-int nghttp2_stream_attach_data(nghttp2_stream *stream,
-                               nghttp2_outbound_item *data_item,
+int nghttp2_stream_attach_item(nghttp2_stream *stream,
+                               nghttp2_outbound_item *item,
                                nghttp2_session *session);
 
 /*
- * Detaches |stream->data_item|.  Updates dpri members in this
- * dependency tree.  This function does not free |stream->data_item|.
- * The caller must free it.
+ * Detaches |stream->item|.  Updates dpri members in this dependency
+ * tree.  This function does not free |stream->item|.  The caller must
+ * free it.
  *
  * This function returns 0 if it succeeds, or one of the following
  * negative error codes:
@@ -346,7 +346,7 @@ int nghttp2_stream_attach_data(nghttp2_stream *stream,
  * NGHTTP2_ERR_NOMEM
  *     Out of memory
  */
-int nghttp2_stream_detach_data(nghttp2_stream *stream,
+int nghttp2_stream_detach_item(nghttp2_stream *stream,
                                nghttp2_session *session);
 
 /*
diff --git a/tests/main.c b/tests/main.c
index 4093abc5..408d5074 100644
--- a/tests/main.c
+++ b/tests/main.c
@@ -231,10 +231,10 @@ int main(int argc _U_, char *argv[] _U_) {
       !CU_add_test(
           pSuite, "session_stream_dep_all_your_stream_are_belong_to_us",
           test_nghttp2_session_stream_dep_all_your_stream_are_belong_to_us) ||
-      !CU_add_test(pSuite, "session_stream_attach_data",
-                   test_nghttp2_session_stream_attach_data) ||
-      !CU_add_test(pSuite, "session_stream_attach_data_subtree",
-                   test_nghttp2_session_stream_attach_data_subtree) ||
+      !CU_add_test(pSuite, "session_stream_attach_item",
+                   test_nghttp2_session_stream_attach_item) ||
+      !CU_add_test(pSuite, "session_stream_attach_item_subtree",
+                   test_nghttp2_session_stream_attach_item_subtree) ||
       !CU_add_test(pSuite, "session_stream_keep_closed_stream",
                    test_nghttp2_session_keep_closed_stream) ||
       !CU_add_test(pSuite, "session_stream_keep_idle_stream",
diff --git a/tests/nghttp2_session_test.c b/tests/nghttp2_session_test.c
index de10c923..61e3b0f0 100644
--- a/tests/nghttp2_session_test.c
+++ b/tests/nghttp2_session_test.c
@@ -2495,7 +2495,7 @@ void test_nghttp2_session_on_window_update_received(void) {
 
   data_item = create_data_ob_item();
 
-  CU_ASSERT(0 == nghttp2_stream_attach_data(stream, data_item, session));
+  CU_ASSERT(0 == nghttp2_stream_attach_item(stream, data_item, session));
 
   nghttp2_frame_window_update_init(&frame.window_update, NGHTTP2_FLAG_NONE, 1,
                                    16 * 1024);
@@ -2506,7 +2506,7 @@ void test_nghttp2_session_on_window_update_received(void) {
             stream->remote_window_size);
 
   CU_ASSERT(0 ==
-            nghttp2_stream_defer_data(
+            nghttp2_stream_defer_item(
                 stream, NGHTTP2_STREAM_FLAG_DEFERRED_FLOW_CONTROL, session));
 
   CU_ASSERT(0 == nghttp2_session_on_window_update_received(session, &frame));
@@ -4255,7 +4255,7 @@ void test_nghttp2_session_pop_next_ob_item(void) {
 
   stream = nghttp2_session_get_stream(session, 1);
 
-  nghttp2_stream_detach_data(stream, session);
+  nghttp2_stream_detach_item(stream, session);
 
   nghttp2_outbound_item_free(item, mem);
   free(item);
@@ -4736,9 +4736,9 @@ void test_nghttp2_session_data_read_temporal_failure(void) {
 
   stream = nghttp2_session_get_stream(session, 1);
   CU_ASSERT(nghttp2_stream_check_deferred_by_flow_control(stream));
-  CU_ASSERT(NGHTTP2_DATA == stream->data_item->frame.hd.type);
+  CU_ASSERT(NGHTTP2_DATA == stream->item->frame.hd.type);
 
-  stream->data_item->aux_data.data.data_prd.read_callback =
+  stream->item->aux_data.data.data_prd.read_callback =
       temporal_failure_data_source_read_callback;
 
   /* Back NGHTTP2_INITIAL_WINDOW_SIZE to both connection-level and
@@ -5813,7 +5813,7 @@ void test_nghttp2_session_stream_dep_all_your_stream_are_belong_to_us(void) {
   nghttp2_session_del(session);
 }
 
-void test_nghttp2_session_stream_attach_data(void) {
+void test_nghttp2_session_stream_attach_item(void) {
   nghttp2_session *session;
   nghttp2_session_callbacks callbacks;
   nghttp2_stream *a, *b, *c, *d;
@@ -5837,12 +5837,12 @@ void test_nghttp2_session_stream_attach_data(void) {
 
   db = create_data_ob_item();
 
-  nghttp2_stream_attach_data(b, db, session);
+  nghttp2_stream_attach_item(b, db, session);
 
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == a->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == a->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == b->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == c->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == d->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == c->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == d->dpri);
 
   CU_ASSERT(16 == b->effective_weight);
 
@@ -5852,12 +5852,12 @@ void test_nghttp2_session_stream_attach_data(void) {
 
   dc = create_data_ob_item();
 
-  nghttp2_stream_attach_data(c, dc, session);
+  nghttp2_stream_attach_item(c, dc, session);
 
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == a->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == a->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == b->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == c->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == d->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == d->dpri);
 
   CU_ASSERT(16 * 16 / 32 == b->effective_weight);
   CU_ASSERT(16 * 16 / 32 == c->effective_weight);
@@ -5868,32 +5868,32 @@ void test_nghttp2_session_stream_attach_data(void) {
 
   da = create_data_ob_item();
 
-  nghttp2_stream_attach_data(a, da, session);
+  nghttp2_stream_attach_item(a, da, session);
 
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == a->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_REST == b->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_REST == c->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == d->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == d->dpri);
 
   CU_ASSERT(16 == a->effective_weight);
 
   CU_ASSERT(1 == da->queued);
 
-  nghttp2_stream_detach_data(a, session);
+  nghttp2_stream_detach_item(a, session);
 
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == a->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == a->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == b->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == c->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == d->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == d->dpri);
 
   CU_ASSERT(16 * 16 / 32 == b->effective_weight);
   CU_ASSERT(16 * 16 / 32 == c->effective_weight);
 
   dd = create_data_ob_item();
 
-  nghttp2_stream_attach_data(d, dd, session);
+  nghttp2_stream_attach_item(d, dd, session);
 
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == a->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == a->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == b->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == c->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_REST == d->dpri);
@@ -5903,22 +5903,22 @@ void test_nghttp2_session_stream_attach_data(void) {
 
   CU_ASSERT(0 == dd->queued);
 
-  nghttp2_stream_detach_data(c, session);
+  nghttp2_stream_detach_item(c, session);
 
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == a->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == a->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == b->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == c->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == c->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_REST == d->dpri);
 
   CU_ASSERT(16 * 16 / 16 == b->effective_weight);
 
   CU_ASSERT(0 == dd->queued);
 
-  nghttp2_stream_detach_data(b, session);
+  nghttp2_stream_detach_item(b, session);
 
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == a->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == b->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == c->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == a->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == b->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == c->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == d->dpri);
 
   CU_ASSERT(16 * 16 / 16 == d->effective_weight);
@@ -5928,7 +5928,7 @@ void test_nghttp2_session_stream_attach_data(void) {
   nghttp2_session_del(session);
 }
 
-void test_nghttp2_session_stream_attach_data_subtree(void) {
+void test_nghttp2_session_stream_attach_item_subtree(void) {
   nghttp2_session *session;
   nghttp2_session_callbacks callbacks;
   nghttp2_stream *a, *b, *c, *d, *e, *f;
@@ -5955,18 +5955,18 @@ void test_nghttp2_session_stream_attach_data_subtree(void) {
 
   de = create_data_ob_item();
 
-  nghttp2_stream_attach_data(e, de, session);
+  nghttp2_stream_attach_item(e, de, session);
 
   db = create_data_ob_item();
 
-  nghttp2_stream_attach_data(b, db, session);
+  nghttp2_stream_attach_item(b, db, session);
 
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == a->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == a->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == b->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == c->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == d->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == c->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == d->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == e->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == f->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == f->dpri);
 
   CU_ASSERT(16 == b->effective_weight);
   CU_ASSERT(16 == e->effective_weight);
@@ -5986,12 +5986,12 @@ void test_nghttp2_session_stream_attach_data_subtree(void) {
    *    d
    */
 
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == a->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == a->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_REST == b->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == c->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == d->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == c->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == d->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == e->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == f->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == f->dpri);
 
   CU_ASSERT(16 == e->effective_weight);
 
@@ -6011,12 +6011,12 @@ void test_nghttp2_session_stream_attach_data_subtree(void) {
    *    d
    */
 
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == a->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == a->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == b->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == c->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == d->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == c->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == d->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == e->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == f->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == f->dpri);
 
   CU_ASSERT(16 == b->effective_weight);
   CU_ASSERT(16 == e->effective_weight);
@@ -6027,12 +6027,12 @@ void test_nghttp2_session_stream_attach_data_subtree(void) {
 
   nghttp2_stream_dep_make_root(a, session);
 
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == a->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == a->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == b->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == c->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == d->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == c->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == d->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == e->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == f->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == f->dpri);
 
   /* Remove subtree c */
 
@@ -6048,16 +6048,16 @@ void test_nghttp2_session_stream_attach_data_subtree(void) {
    * f
    */
 
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == a->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == a->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == b->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == c->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == d->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == c->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == d->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == e->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == f->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == f->dpri);
 
   dd = create_data_ob_item();
 
-  nghttp2_stream_attach_data(d, dd, session);
+  nghttp2_stream_attach_item(d, dd, session);
 
   /* Add subtree c to a */
 
@@ -6072,12 +6072,12 @@ void test_nghttp2_session_stream_attach_data_subtree(void) {
    * d  f
    */
 
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == a->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == a->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == b->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == c->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == c->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_REST == d->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == e->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == f->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == f->dpri);
 
   CU_ASSERT(16 == b->effective_weight);
   CU_ASSERT(16 * 16 / 16 == e->effective_weight);
@@ -6100,12 +6100,12 @@ void test_nghttp2_session_stream_attach_data_subtree(void) {
    * f  d
    */
 
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == a->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == a->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == b->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == c->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == c->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_REST == d->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_REST == e->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == f->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == f->dpri);
 
   CU_ASSERT(16 == b->effective_weight);
 
@@ -6125,12 +6125,12 @@ void test_nghttp2_session_stream_attach_data_subtree(void) {
    * f  d
    */
 
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == a->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == a->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_TOP == b->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == c->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == c->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_REST == d->dpri);
   CU_ASSERT(NGHTTP2_STREAM_DPRI_REST == e->dpri);
-  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_DATA == f->dpri);
+  CU_ASSERT(NGHTTP2_STREAM_DPRI_NO_ITEM == f->dpri);
 
   CU_ASSERT(0 == a->sum_norest_weight);
   CU_ASSERT(0 == b->sum_norest_weight);
diff --git a/tests/nghttp2_session_test.h b/tests/nghttp2_session_test.h
index 2513281d..2cb393d1 100644
--- a/tests/nghttp2_session_test.h
+++ b/tests/nghttp2_session_test.h
@@ -108,8 +108,8 @@ void test_nghttp2_session_stream_dep_remove(void);
 void test_nghttp2_session_stream_dep_add_subtree(void);
 void test_nghttp2_session_stream_dep_remove_subtree(void);
 void test_nghttp2_session_stream_dep_all_your_stream_are_belong_to_us(void);
-void test_nghttp2_session_stream_attach_data(void);
-void test_nghttp2_session_stream_attach_data_subtree(void);
+void test_nghttp2_session_stream_attach_item(void);
+void test_nghttp2_session_stream_attach_item_subtree(void);
 void test_nghttp2_session_keep_closed_stream(void);
 void test_nghttp2_session_keep_idle_stream(void);
 void test_nghttp2_session_detach_idle_stream(void);