diff --git a/core/bootstrap/primitives.factor b/core/bootstrap/primitives.factor
index a5348db973..5836b4d3c5 100755
--- a/core/bootstrap/primitives.factor
+++ b/core/bootstrap/primitives.factor
@@ -30,7 +30,7 @@ crossref off
 ! Bring up a bare cross-compiling vocabulary.
 "syntax" vocab vocab-words bootstrap-syntax set
 H{ } clone dictionary set
-H{ } clone changed-words set
+H{ } clone changed-definitions set
 H{ } clone forgotten-definitions set
 H{ } clone root-cache set
 H{ } clone source-files set
diff --git a/core/classes/tuple/tuple.factor b/core/classes/tuple/tuple.factor
index 8b5972417d..1aa283a675 100755
--- a/core/classes/tuple/tuple.factor
+++ b/core/classes/tuple/tuple.factor
@@ -174,7 +174,7 @@ M: tuple-class update-class
         2drop
         [
             [ update-tuples-after ]
-            [ changed-word ]
+            [ changed-definition ]
             [ redefined ]
             tri
         ] each-subclass
diff --git a/core/compiler/units/units.factor b/core/compiler/units/units.factor
index f87c1ec985..a780e0a745 100755
--- a/core/compiler/units/units.factor
+++ b/core/compiler/units/units.factor
@@ -56,12 +56,12 @@ GENERIC: definitions-changed ( assoc obj -- )
     [ drop word? ] assoc-subset
     [ drop word-vocabulary dup [ vocab ] when dup ] assoc-map ;
 
-: changed-definitions ( -- assoc )
+: updated-definitions ( -- assoc )
     H{ } clone
     dup forgotten-definitions get update
     dup new-definitions get first update
     dup new-definitions get second update
-    dup changed-words get update
+    dup changed-definitions get update
     dup dup changed-vocabs update ;
 
 : compile ( words -- )
@@ -73,7 +73,7 @@ SYMBOL: outdated-tuples
 SYMBOL: update-tuples-hook
 
 : call-recompile-hook ( -- )
-    changed-words get keys
+    changed-definitions get keys [ word? ] subset
     compiled-usages recompile-hook get call ;
 
 : call-update-tuples-hook ( -- )
@@ -83,11 +83,11 @@ SYMBOL: update-tuples-hook
     call-recompile-hook
     call-update-tuples-hook
     dup [ drop crossref? ] assoc-contains? modify-code-heap
-    changed-definitions notify-definition-observers ;
+    updated-definitions notify-definition-observers ;
 
 : with-compilation-unit ( quot -- )
     [
-        H{ } clone changed-words set
+        H{ } clone changed-definitions set
         H{ } clone forgotten-definitions set
         H{ } clone outdated-tuples set
         <definitions> new-definitions set
diff --git a/core/definitions/definitions.factor b/core/definitions/definitions.factor
index 6ee21fc016..459512b83a 100755
--- a/core/definitions/definitions.factor
+++ b/core/definitions/definitions.factor
@@ -5,6 +5,13 @@ USING: kernel sequences namespaces assocs graphs ;
 
 ERROR: no-compilation-unit definition ;
 
+SYMBOL: changed-definitions
+
+: changed-definition ( defspec -- )
+    dup changed-definitions get
+    [ no-compilation-unit ] unless*
+    set-at ;
+
 GENERIC: where ( defspec -- loc )
 
 M: object where drop f ;
diff --git a/core/words/words.factor b/core/words/words.factor
index 2510c50347..7794a7f41f 100755
--- a/core/words/words.factor
+++ b/core/words/words.factor
@@ -144,19 +144,12 @@ PRIVATE>
 : redefined ( word -- )
     H{ } clone visited [ (redefined) ] with-variable ;
 
-SYMBOL: changed-words
-
-: changed-word ( word -- )
-    dup changed-words get
-    [ no-compilation-unit ] unless*
-    set-at ;
-
 : define ( word def -- )
     [ ] like
     over unxref
     over redefined
     over set-word-def
-    dup changed-word
+    dup changed-definition
     dup crossref? [ dup xref ] when drop ;
 
 : define-declared ( word def effect -- )
diff --git a/extra/help/syntax/syntax.factor b/extra/help/syntax/syntax.factor
index 9450f87215..65120a5d01 100755
--- a/extra/help/syntax/syntax.factor
+++ b/extra/help/syntax/syntax.factor
@@ -1,4 +1,4 @@
-! Copyright (C) 2005, 2007 Slava Pestov.
+! Copyright (C) 2005, 2008 Slava Pestov.
 ! See http://factorcode.org/license.txt for BSD license.
 USING: arrays kernel parser sequences words help help.topics
 namespaces vocabs definitions compiler.units ;
@@ -16,4 +16,7 @@ IN: help.syntax
     over add-article >link r> remember-definition ; parsing
 
 : ABOUT:
-    scan-object in get vocab set-vocab-help ; parsing
+    scan-object
+    in get vocab
+    dup changed-definition
+    set-vocab-help ; parsing