diff --git a/README.md b/README.md
index d252736bf..62bbf96b8 100644
--- a/README.md
+++ b/README.md
@@ -928,6 +928,20 @@ __Please note__: If the keyword is validating data type that is different from t
 See [Defining custom keywords](#defining-custom-keywords) for more details.
 
 
+##### .getKeyword(String keyword) -> Object|Boolean
+
+Returns custom keyword definition, `true` for pre-defined keywords and `false` if the keyword is unknown.
+
+
+##### .removeKeyword(String keyword)
+
+Removes custom or pre-defined keyword so you can redefine them.
+
+While this method can be used to extend pre-defined keywords, it can also be used to completely change their meaning - it may lead to unexpected results.
+
+__Please note__: schemas compiled before the keyword is removed will continue to work without changes. To recompile schemas use `removeSchema` method and compile them again.
+
+
 ##### .errorsText([Array<Object> errors [, Object options]]) -> String
 
 Returns the text with all errors in a String.
diff --git a/lib/ajv.d.ts b/lib/ajv.d.ts
index 9a9d3a6ee..0e10c9a67 100644
--- a/lib/ajv.d.ts
+++ b/lib/ajv.d.ts
@@ -74,6 +74,19 @@ declare namespace ajv {
     */
     addKeyword(keyword: string, definition: KeywordDefinition): void;
     /**
+    * Get keyword definition
+    * @this  Ajv
+    * @param {String} keyword pre-defined or custom keyword.
+    * @return {Object|Boolean} custom keyword definition, `true` if it is a predefined keyword, `false` otherwise.
+    */
+    getKeyword(keyword: string): Object | boolean;
+    /**
+    * Remove keyword
+    * @this  Ajv
+    * @param {String} keyword pre-defined or custom keyword.
+    */
+    removeKeyword(keyword: string): void;
+    /**
     * Convert array of error message objects to string
     * @param  {Array<Object>} errors optional array of validation errors, if not passed errors from the instance are used.
     * @param  {Object} options optional options with properties `separator` and `dataVar`.
diff --git a/lib/keyword.js b/lib/keyword.js
index e7cabde90..954bacaf1 100644
--- a/lib/keyword.js
+++ b/lib/keyword.js
@@ -91,7 +91,7 @@ function addKeyword(keyword, definition) {
 
 
 /**
- * Get custom keyword
+ * Get keyword
  * @this  Ajv
  * @param {String} keyword pre-defined or custom keyword.
  * @return {Object|Boolean} custom keyword definition, `true` if it is a predefined keyword, `false` otherwise.
diff --git a/package.json b/package.json
index b8d6f3ad2..aea85f31d 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "ajv",
-  "version": "4.9.3",
+  "version": "4.10.0",
   "description": "Another JSON Schema Validator",
   "main": "lib/ajv.js",
   "webpack": "dist/ajv.bundle.js",