diff --git a/library/HTMLPurifier.php b/library/HTMLPurifier.php
index c46ccf15..2b9f0e95 100644
--- a/library/HTMLPurifier.php
+++ b/library/HTMLPurifier.php
@@ -21,7 +21,7 @@
 require_once 'HTMLPurifier/ConfigDef.php';
 require_once 'HTMLPurifier/Config.php';
 require_once 'HTMLPurifier/Lexer.php';
-require_once 'HTMLPurifier/Definition.php';
+require_once 'HTMLPurifier/HTMLDefinition.php';
 require_once 'HTMLPurifier/Generator.php';
 require_once 'HTMLPurifier/Strategy/Core.php';
 
diff --git a/library/HTMLPurifier/Definition.php b/library/HTMLPurifier/HTMLDefinition.php
similarity index 99%
rename from library/HTMLPurifier/Definition.php
rename to library/HTMLPurifier/HTMLDefinition.php
index e2e852e4..fe795246 100644
--- a/library/HTMLPurifier/Definition.php
+++ b/library/HTMLPurifier/HTMLDefinition.php
@@ -41,7 +41,7 @@ require_once 'HTMLPurifier/TagTransform.php';
  * automatic recompilation, suggesting that we would have a DefinitionGenerator.
  */
 
-class HTMLPurifier_Definition
+class HTMLPurifier_HTMLDefinition
 {
     
     var $info = array();
@@ -68,13 +68,13 @@ class HTMLPurifier_Definition
         if ($prototype) {
             $instance = $prototype;
         } elseif (!$instance) {
-            $instance = new HTMLPurifier_Definition();
+            $instance = new HTMLPurifier_HTMLDefinition();
             $instance->setup();
         }
         return $instance;
     }
     
-    function HTMLPurifier_Definition() {}
+    function HTMLPurifier_HTMLDefinition() {}
     
     function setup() {
         
diff --git a/library/HTMLPurifier/Strategy/FixNesting.php b/library/HTMLPurifier/Strategy/FixNesting.php
index 7b04c534..1585147e 100644
--- a/library/HTMLPurifier/Strategy/FixNesting.php
+++ b/library/HTMLPurifier/Strategy/FixNesting.php
@@ -1,7 +1,7 @@
 <?php
 
 require_once 'HTMLPurifier/Strategy.php';
-require_once 'HTMLPurifier/Definition.php';
+require_once 'HTMLPurifier/HTMLDefinition.php';
 
 /**
  * Takes a well formed list of tokens and fixes their nesting.
@@ -37,7 +37,7 @@ class HTMLPurifier_Strategy_FixNesting extends HTMLPurifier_Strategy
     var $definition;
     
     function HTMLPurifier_Strategy_FixNesting() {
-        $this->definition = HTMLPurifier_Definition::instance();
+        $this->definition = HTMLPurifier_HTMLDefinition::instance();
     }
     
     function execute($tokens, $config) {
diff --git a/library/HTMLPurifier/Strategy/MakeWellFormed.php b/library/HTMLPurifier/Strategy/MakeWellFormed.php
index d3f6b8bb..6284f2b3 100644
--- a/library/HTMLPurifier/Strategy/MakeWellFormed.php
+++ b/library/HTMLPurifier/Strategy/MakeWellFormed.php
@@ -1,7 +1,7 @@
 <?php
 
 require_once 'HTMLPurifier/Strategy.php';
-require_once 'HTMLPurifier/Definition.php';
+require_once 'HTMLPurifier/HTMLDefinition.php';
 require_once 'HTMLPurifier/Generator.php';
 
 class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy
@@ -12,7 +12,7 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy
     
     function HTMLPurifier_Strategy_MakeWellFormed() {
         $this->generator = new HTMLPurifier_Generator();
-        $this->definition = HTMLPurifier_Definition::instance();
+        $this->definition = HTMLPurifier_HTMLDefinition::instance();
     }
     
     function execute($tokens, $config) {
diff --git a/library/HTMLPurifier/Strategy/RemoveForeignElements.php b/library/HTMLPurifier/Strategy/RemoveForeignElements.php
index f1d0e79f..c6f66d97 100644
--- a/library/HTMLPurifier/Strategy/RemoveForeignElements.php
+++ b/library/HTMLPurifier/Strategy/RemoveForeignElements.php
@@ -1,7 +1,7 @@
 <?php
 
 require_once 'HTMLPurifier/Strategy.php';
-require_once 'HTMLPurifier/Definition.php';
+require_once 'HTMLPurifier/HTMLDefinition.php';
 require_once 'HTMLPurifier/Generator.php';
 require_once 'HTMLPurifier/TagTransform.php';
 
@@ -21,7 +21,7 @@ class HTMLPurifier_Strategy_RemoveForeignElements extends HTMLPurifier_Strategy
     
     function HTMLPurifier_Strategy_RemoveForeignElements() {
         $this->generator = new HTMLPurifier_Generator();
-        $this->definition = HTMLPurifier_Definition::instance();
+        $this->definition = HTMLPurifier_HTMLDefinition::instance();
     }
     
     function execute($tokens, $config) {
diff --git a/library/HTMLPurifier/Strategy/ValidateAttributes.php b/library/HTMLPurifier/Strategy/ValidateAttributes.php
index 995b28b3..12cc892b 100644
--- a/library/HTMLPurifier/Strategy/ValidateAttributes.php
+++ b/library/HTMLPurifier/Strategy/ValidateAttributes.php
@@ -1,7 +1,7 @@
 <?php
 
 require_once 'HTMLPurifier/Strategy.php';
-require_once 'HTMLPurifier/Definition.php';
+require_once 'HTMLPurifier/HTMLDefinition.php';
 require_once 'HTMLPurifier/IDAccumulator.php';
 require_once 'HTMLPurifier/ConfigDef.php';
 require_once 'HTMLPurifier/AttrContext.php';
@@ -20,7 +20,7 @@ class HTMLPurifier_Strategy_ValidateAttributes extends HTMLPurifier_Strategy
     var $definition;
     
     function HTMLPurifier_Strategy_ValidateAttributes() {
-        $this->definition = HTMLPurifier_Definition::instance();
+        $this->definition = HTMLPurifier_HTMLDefinition::instance();
     }
     
     function execute($tokens, $config) {
diff --git a/tests/HTMLPurifier/StrategyHarness.php b/tests/HTMLPurifier/StrategyHarness.php
index 27c0c71d..4c257aea 100644
--- a/tests/HTMLPurifier/StrategyHarness.php
+++ b/tests/HTMLPurifier/StrategyHarness.php
@@ -1,6 +1,5 @@
 <?php
 
-require_once 'HTMLPurifier/Definition.php';
 require_once 'HTMLPurifier/Lexer/DirectLex.php';
 
 class HTMLPurifier_StrategyHarness extends UnitTestCase