diff --git a/hyper-schema-output.json b/hyper-schema-output.json
index 32bba5df..5c2a9786 100644
--- a/hyper-schema-output.json
+++ b/hyper-schema-output.json
@@ -4,7 +4,7 @@
     "type": "array",
     "items": {
         "allOf": [
-            {"$ref": "http://json-schema.org/draft-08/links#/definitions/noRequiredFields" }
+            {"$ref": "http://json-schema.org/draft-08/links#/$defs/noRequiredFields" }
         ],
         "type": "object",
         "required": [
diff --git a/hyper-schema.json b/hyper-schema.json
index 4841cd55..82cf32fa 100644
--- a/hyper-schema.json
+++ b/hyper-schema.json
@@ -2,10 +2,10 @@
     "$schema": "http://json-schema.org/draft-08/hyper-schema#",
     "$id": "http://json-schema.org/draft-08/hyper-schema#",
     "title": "JSON Hyper-Schema",
-    "definitions": {
+    "$defs": {
         "schemaArray": {
             "allOf": [
-                { "$ref": "http://json-schema.org/draft-08/schema#/definitions/schemaArray" },
+                { "$ref": "http://json-schema.org/draft-08/schema#/$defs/schemaArray" },
                 {
                     "items": { "$ref": "#" }
                 }
@@ -27,10 +27,14 @@
         "items": {
             "anyOf": [
                 { "$ref": "#" },
-                { "$ref": "#/definitions/schemaArray" }
+                { "$ref": "#/$defs/schemaArray" }
             ]
         },
+        "$defs": {
+            "additionalProperties": { "$ref": "#" }
+        },
         "definitions": {
+            "$comment": "Renamed to $defs, but retained here to ensure compatibility",
             "additionalProperties": { "$ref": "#" }
         },
         "patternProperties": {
@@ -42,9 +46,9 @@
         "if": {"$ref": "#"},
         "then": {"$ref": "#"},
         "else": {"$ref": "#"},
-        "allOf": { "$ref": "#/definitions/schemaArray" },
-        "anyOf": { "$ref": "#/definitions/schemaArray" },
-        "oneOf": { "$ref": "#/definitions/schemaArray" },
+        "allOf": { "$ref": "#/$defs/schemaArray" },
+        "anyOf": { "$ref": "#/$defs/schemaArray" },
+        "oneOf": { "$ref": "#/$defs/schemaArray" },
         "not": { "$ref": "#" },
         "contains": { "$ref": "#" },
         "propertyNames": { "$ref": "#" },
diff --git a/jsonschema-core.xml b/jsonschema-core.xml
index 4d04ab69..c3b63621 100644
--- a/jsonschema-core.xml
+++ b/jsonschema-core.xml
@@ -629,11 +629,11 @@
 <![CDATA[
 {
     "$id": "http://example.com/root.json",
-    "definitions": {
+    "$defs": {
         "A": { "$id": "#foo" },
         "B": {
             "$id": "other.json",
-            "definitions": {
+            "$defs": {
                 "X": { "$id": "#bar" },
                 "Y": { "$id": "t/inner.json" }
             }
@@ -660,39 +660,39 @@
                                     <t>http://example.com/root.json#</t>
                                 </list>
                             </t>
-                            <t hangText="#/definitions/A">
+                            <t hangText="#/$defs/A">
                                 <list>
                                     <t>http://example.com/root.json#foo</t>
-                                    <t>http://example.com/root.json#/definitions/A</t>
+                                    <t>http://example.com/root.json#/$defs/A</t>
                                 </list>
                             </t>
-                            <t hangText="#/definitions/B">
+                            <t hangText="#/$defs/B">
                                 <list>
                                     <t>http://example.com/other.json</t>
                                     <t>http://example.com/other.json#</t>
-                                    <t>http://example.com/root.json#/definitions/B</t>
+                                    <t>http://example.com/root.json#/$defs/B</t>
                                 </list>
                             </t>
-                            <t hangText="#/definitions/B/definitions/X">
+                            <t hangText="#/$defs/B/$defs/X">
                                 <list>
                                     <t>http://example.com/other.json#bar</t>
-                                    <t>http://example.com/other.json#/definitions/X</t>
-                                    <t>http://example.com/root.json#/definitions/B/definitions/X</t>
+                                    <t>http://example.com/other.json#/$defs/X</t>
+                                    <t>http://example.com/root.json#/$defs/B/$defs/X</t>
                                 </list>
                             </t>
-                            <t hangText="#/definitions/B/definitions/Y">
+                            <t hangText="#/$defs/B/$defs/Y">
                                 <list>
                                     <t>http://example.com/t/inner.json</t>
                                     <t>http://example.com/t/inner.json#</t>
-                                    <t>http://example.com/other.json#/definitions/Y</t>
-                                    <t>http://example.com/root.json#/definitions/B/definitions/Y</t>
+                                    <t>http://example.com/other.json#/$defs/Y</t>
+                                    <t>http://example.com/root.json#/$defs/B/$defs/Y</t>
                                 </list>
                             </t>
-                            <t hangText="#/definitions/C">
+                            <t hangText="#/$defs/C">
                                 <list>
                                     <t>urn:uuid:ee564b8a-7a87-4125-8c96-e9f123d6766f</t>
                                     <t>urn:uuid:ee564b8a-7a87-4125-8c96-e9f123d6766f#</t>
-                                    <t>http://example.com/root.json#/definitions/C</t>
+                                    <t>http://example.com/root.json#/$defs/C</t>
                                 </list>
                             </t>
                         </list>
@@ -776,7 +776,7 @@
         "type": "array",
         "items": { "$ref": "#item" }
     },
-    "definitions": {
+    "$defs": {
         "single": {
             "$id": "#item",
             "type": "object",
@@ -788,7 +788,7 @@
                         </artwork>
                     </figure>
                     <t>
-                        When an implementation encounters the &lt;#/definitions/single&gt; schema,
+                        When an implementation encounters the &lt;#/$defs/single&gt; schema,
                         it resolves the "$id" URI reference against the current base URI to form
                         &lt;http://example.net/root.json#item&gt;.
                     </t>
@@ -814,6 +814,40 @@
                     </t>
                 </section>
             </section>
+
+            <section title='Schema Re-Use With "$defs"'>
+                <t>
+                    The "$defs" keyword provides a standardized location for schema
+                    authors to inline re-usable JSON Schemas into a more general schema.
+                    The keyword does not directly affect the validation result.
+                </t>
+                <t>
+                    This keyword's value MUST be an object.
+                    Each member value of this object MUST be a valid JSON Schema.
+                </t>
+                <t>
+                    As an example, here is a schema describing an array of positive
+                    integers, where the positive integer constraint is a subschema in
+                    "$defs":
+
+                    <figure>
+                        <artwork>
+<![CDATA[
+{
+    "type": "array",
+    "items": { "$ref": "#/$defs/positiveInteger" },
+    "$defs": {
+        "positiveInteger": {
+            "type": "integer",
+            "exclusiveMinimum": 0
+        }
+    }
+}
+]]>
+                        </artwork>
+                    </figure>
+                </t>
+            </section>
         </section>
 
         <section title='Comments With "$comment"'>
@@ -1172,7 +1206,7 @@ User-Agent: product-name/5.4.1 so-cool-json-schema/1.0.2 curl/7.43.0
                 <list style="hanging">
                     <t hangText="draft-handrews-json-schema-02">
                         <list style="symbols">
-                            <t></t>
+                            <t>Moved "definitions" from the Validation specification here as "$defs"</t>
                         </list>
                     </t>
                     <t hangText="draft-handrews-json-schema-01">
diff --git a/jsonschema-hyperschema.xml b/jsonschema-hyperschema.xml
index 3bfbd98d..5631b0da 100644
--- a/jsonschema-hyperschema.xml
+++ b/jsonschema-hyperschema.xml
@@ -1628,7 +1628,7 @@ Link: <https://schema.example.com/entry> rel=describedBy
     "type": "object",
     "required": ["data"],
     "properties": {
-        "id": {"$ref": "#/definitions/id"},
+        "id": {"$ref": "#/$defs/id"},
         "data": true
     },
     "links": [
@@ -1639,7 +1639,7 @@ Link: <https://schema.example.com/entry> rel=describedBy
             "targetSchema": {"$ref": "#"}
         }
     ],
-    "definitions": {
+    "$defs": {
         "id": {
             "type": "integer",
             "minimum": 1,
@@ -1652,7 +1652,7 @@ Link: <https://schema.example.com/entry> rel=describedBy
                 <t>
                     Our "thing" has a server-assigned id, which is required in order to
                     construct the "self" link.  It also has a "data" field which can be
-                    of any type.  The reason for the "definitions" section will be clear
+                    of any type.  The reason for the "$defs" section will be clear
                     in the next example.
                 </t>
                 <t>
@@ -1678,7 +1678,7 @@ Link: <https://schema.example.com/entry> rel=describedBy
     "hrefSchema": {
         "required": ["id"],
         "properties": {
-            "id": {"$ref": "thing#/definitions/id"}
+            "id": {"$ref": "thing#/$defs/id"}
         }
     },
     "targetSchema": {"$ref": "thing#"}
@@ -1993,7 +1993,7 @@ Link: <https://api.example.com/trees/1/nodes/456> rev=up
     "type": "object",
     "required": ["data"],
     "properties": {
-        "id": {"$ref": "#/definitions/id"},
+        "id": {"$ref": "#/$defs/id"},
         "data": true
     },
     "links": [
@@ -2009,7 +2009,7 @@ Link: <https://api.example.com/trees/1/nodes/456> rev=up
             "submissionSchema": {"$ref": "#"}
         }
     ],
-    "definitions": {
+    "$defs": {
         "id": {
             "type": "integer",
             "minimum": 1,
@@ -2206,9 +2206,9 @@ Link: <https://api.example.com/trees/1/nodes/456> rev=up
         "meta": {
             "type": "object",
             "properties": {
-                "prev": {"$ref": "#/definitions/pagination"},
-                "current": {"$ref": "#/definitions/pagination"},
-                "next": {"$ref": "#/definitions/pagination"}
+                "prev": {"$ref": "#/$defs/pagination"},
+                "current": {"$ref": "#/$defs/pagination"},
+                "next": {"$ref": "#/$defs/pagination"}
             }
         }
     },
@@ -2242,7 +2242,7 @@ Link: <https://api.example.com/trees/1/nodes/456> rev=up
             "targetSchema": {"$ref": "#"}
         }
     ],
-    "definitions": {
+    "$defs": {
         "pagination": {
             "type": "object",
             "properties": {
@@ -2348,7 +2348,7 @@ Link: <https://api.example.com/trees/1/nodes/456> rev=up
     "rel": "tag:rel.example.com,2017:thing-collection",
     "href": "/things{?offset,limit}",
     "hrefSchema": {
-        "$ref": "thing-collection#/definitions/pagination"
+        "$ref": "thing-collection#/$defs/pagination"
     },
     "submissionSchema": {
         "$ref": "thing#"
diff --git a/jsonschema-validation.xml b/jsonschema-validation.xml
index a2c751af..1d1d6ed9 100644
--- a/jsonschema-validation.xml
+++ b/jsonschema-validation.xml
@@ -1233,40 +1233,6 @@
 
         </section>
 
-        <section title='Schema Re-Use With "definitions"'>
-            <t>
-                The "definitions" keywords provides a standardized location for schema
-                authors to inline re-usable JSON Schemas into a more general schema.
-                The keyword does not directly affect the validation result.
-            </t>
-            <t>
-                This keyword's value MUST be an object.
-                Each member value of this object MUST be a valid JSON Schema.
-            </t>
-            <t>
-                As an example, here is a schema describing an array of positive
-                integers, where the positive integer constraint is a subschema in
-                "definitions":
-
-                <figure>
-                    <artwork>
-<![CDATA[
-{
-    "type": "array",
-    "items": { "$ref": "#/definitions/positiveInteger" },
-    "definitions": {
-        "positiveInteger": {
-            "type": "integer",
-            "exclusiveMinimum": 0
-        }
-    }
-}
-]]>
-                    </artwork>
-                </figure>
-            </t>
-        </section>
-
         <section title="Schema Annotations">
             <t>
                 Schema validation is a useful mechanism for annotating instance data
@@ -1470,6 +1436,23 @@
             &RFC4329;
         </references>
 
+        <section title="Keywords Moved from Validation to Core">
+            <t>
+                Several keywords have been moved from this document into the
+                <xref target="json-schema">Core Specification</xref> as of this draft, in some
+                cases with re-naming or other changes.  This affects the following former
+                validation keywords:
+                <list style="hanging">
+                    <t hangText='"definitions"'>
+                        Renamed to "$defs" to match "$ref" and be shorter to type.
+                        Schema vocabulary authors SHOULD NOT define a "definitions" keyword
+                        with different behavior in order to avoid invalidating schemas that
+                        still use the older name.
+                    </t>
+                </list>
+            </t>
+        </section>
+
         <section title="Acknowledgments">
             <t>
                 Thanks to
@@ -1503,7 +1486,7 @@
                 <list style="hanging">
                     <t hangText="draft-handrews-json-schema-validation-02">
                         <list style="symbols">
-                            <t></t>
+                            <t>Moved "definitions" to the core spec as "$defs"</t>
                         </list>
                     </t>
                     <t hangText="draft-handrews-json-schema-validation-01">
diff --git a/links.json b/links.json
index c95b7bd3..addd1f06 100644
--- a/links.json
+++ b/links.json
@@ -4,9 +4,9 @@
     "title": "Link Description Object",
     "allOf": [
         { "required": [ "rel", "href" ] },
-        { "$ref": "#/definitions/noRequiredFields" }
+        { "$ref": "#/$defs/noRequiredFields" }
     ],
-    "definitions": {
+    "$defs": {
         "noRequiredFields": {
             "type": "object",
             "properties": {
diff --git a/schema.json b/schema.json
index 8632f19f..182eefb0 100644
--- a/schema.json
+++ b/schema.json
@@ -2,7 +2,7 @@
     "$schema": "http://json-schema.org/draft-08/schema#",
     "$id": "http://json-schema.org/draft-08/schema#",
     "title": "Core schema meta-schema",
-    "definitions": {
+    "$defs": {
         "schemaArray": {
             "type": "array",
             "minItems": 1,
@@ -14,7 +14,7 @@
         },
         "nonNegativeIntegerDefault0": {
             "allOf": [
-                { "$ref": "#/definitions/nonNegativeInteger" },
+                { "$ref": "#/$defs/nonNegativeInteger" },
                 { "default": 0 }
             ]
         },
@@ -53,6 +53,17 @@
         "$comment": {
             "type": "string"
         },
+        "$defs": {
+            "type": "object",
+            "additionalProperties": { "$ref": "#" },
+            "default": {}
+        },
+        "definitions": {
+            "$comment": "While no longer an official keyword as it is replaced by $defs, this keyword is retained in the meta-schema to prevent incompatible extensions as it remains in common use.",
+            "type": "object",
+            "additionalProperties": { "$ref": "#" },
+            "default": {}
+        },
         "title": {
             "type": "string"
         },
@@ -84,8 +95,8 @@
         "exclusiveMinimum": {
             "type": "number"
         },
-        "maxLength": { "$ref": "#/definitions/nonNegativeInteger" },
-        "minLength": { "$ref": "#/definitions/nonNegativeIntegerDefault0" },
+        "maxLength": { "$ref": "#/$defs/nonNegativeInteger" },
+        "minLength": { "$ref": "#/$defs/nonNegativeIntegerDefault0" },
         "pattern": {
             "type": "string",
             "format": "regex"
@@ -94,26 +105,21 @@
         "items": {
             "anyOf": [
                 { "$ref": "#" },
-                { "$ref": "#/definitions/schemaArray" }
+                { "$ref": "#/$defs/schemaArray" }
             ],
             "default": true
         },
-        "maxItems": { "$ref": "#/definitions/nonNegativeInteger" },
-        "minItems": { "$ref": "#/definitions/nonNegativeIntegerDefault0" },
+        "maxItems": { "$ref": "#/$defs/nonNegativeInteger" },
+        "minItems": { "$ref": "#/$defs/nonNegativeIntegerDefault0" },
         "uniqueItems": {
             "type": "boolean",
             "default": false
         },
         "contains": { "$ref": "#" },
-        "maxProperties": { "$ref": "#/definitions/nonNegativeInteger" },
-        "minProperties": { "$ref": "#/definitions/nonNegativeIntegerDefault0" },
-        "required": { "$ref": "#/definitions/stringArray" },
+        "maxProperties": { "$ref": "#/$defs/nonNegativeInteger" },
+        "minProperties": { "$ref": "#/$defs/nonNegativeIntegerDefault0" },
+        "required": { "$ref": "#/$defs/stringArray" },
         "additionalProperties": { "$ref": "#" },
-        "definitions": {
-            "type": "object",
-            "additionalProperties": { "$ref": "#" },
-            "default": {}
-        },
         "properties": {
             "type": "object",
             "additionalProperties": { "$ref": "#" },
@@ -130,7 +136,7 @@
             "additionalProperties": {
                 "anyOf": [
                     { "$ref": "#" },
-                    { "$ref": "#/definitions/stringArray" }
+                    { "$ref": "#/$defs/stringArray" }
                 ]
             }
         },
@@ -144,10 +150,10 @@
         },
         "type": {
             "anyOf": [
-                { "$ref": "#/definitions/simpleTypes" },
+                { "$ref": "#/$defs/simpleTypes" },
                 {
                     "type": "array",
-                    "items": { "$ref": "#/definitions/simpleTypes" },
+                    "items": { "$ref": "#/$defs/simpleTypes" },
                     "minItems": 1,
                     "uniqueItems": true
                 }
@@ -159,9 +165,9 @@
         "if": {"$ref": "#"},
         "then": {"$ref": "#"},
         "else": {"$ref": "#"},
-        "allOf": { "$ref": "#/definitions/schemaArray" },
-        "anyOf": { "$ref": "#/definitions/schemaArray" },
-        "oneOf": { "$ref": "#/definitions/schemaArray" },
+        "allOf": { "$ref": "#/$defs/schemaArray" },
+        "anyOf": { "$ref": "#/$defs/schemaArray" },
+        "oneOf": { "$ref": "#/$defs/schemaArray" },
         "not": { "$ref": "#" }
     },
     "default": true