diff --git a/src/metaschema.json b/src/metaschema.json
index f8568c1d25..8fe4099cce 100644
--- a/src/metaschema.json
+++ b/src/metaschema.json
@@ -84,42 +84,19 @@
           "type": "object",
           "patternProperties": {
             "^[a-zA-Z0-9_]+$": {
-              "type": "object",
-              "properties": {
-                "name": {
-                  "type": "string"
-                },
-                "display_name": {
-                  "type": "string"
-                },
-                "description": {
-                  "type": "string"
-                },
-                "type": {
-                  "$ref": "http://json-schema.org/draft/2020-12/meta/validation#/properties/type"
-                },
-                "format": { "$ref": "#/definitions/formats" },
-                "pattern": {
-                  "type": "string"
-                },
-                "unit": {
-                  "type": "string"
-                },
-                "enum": {
-                  "type": "array"
-                },
-                "anyOf": {
-                  "$ref": "http://json-schema.org/draft/2020-12/meta/applicator#/properties/anyOf"
-                },
-                "maximum": {
-                  "type": "number"
-                },
-                "minimum": {
-                  "type": "number"
+              "allOf": [
+                { "$ref": "#/definitions/schemaTerm" },
+                { "$ref": "#/definitions/generalTerm" },
+                { "$ref": "#/definitions/nameValueTerm" },
+                {
+                  "type": "object",
+                  "properties": {
+                    "format": { "$ref": "#/definitions/formats" },
+                    "unit": { "type": "string" }
+                  }
                 }
-              },
-              "required": ["name", "display_name"],
-              "additionalProperties": false
+              ],
+              "unevaluatedProperties": false
             }
           },
           "additionalProperties": false
@@ -128,17 +105,8 @@
           "type": "object",
           "patternProperties": {
             "^[a-zA-Z0-9_]+$": {
-              "type": "object",
-              "properties": {
-                "display_name": {
-                  "type": "string"
-                },
-                "description": {
-                  "type": "string"
-                }
-              },
-              "required": ["display_name", "description"],
-              "additionalProperties": false
+              "$ref": "#/definitions/generalTerm",
+              "unevaluatedProperties": false
             },
             "additionalProperties": false
           }
@@ -147,20 +115,11 @@
           "type": "object",
           "patternProperties": {
             "^[a-zA-Z0-9_]+$": {
-              "type": "object",
-              "properties": {
-                "value": {
-                  "type": "string"
-                },
-                "display_name": {
-                  "type": "string"
-                },
-                "description": {
-                  "type": "string"
-                }
-              },
-              "required": ["value", "display_name", "description"],
-              "additionalProperties": false
+              "allOf": [
+                { "$ref": "#/definitions/generalTerm" },
+                { "$ref": "#/definitions/valueTerm" }
+              ],
+              "unevaluatedProperties": false
             }
           },
           "additionalProperties": false
@@ -169,33 +128,19 @@
           "type": "object",
           "patternProperties": {
             "^[a-zA-Z0-9_]+$": {
-              "type": "object",
-              "properties": {
-                "name": {
-                  "type": "string"
-                },
-                "display_name": {
-                  "type": "string"
-                },
-                "description": {
-                  "type": "string"
-                },
-                "type": {
-                  "$ref": "http://json-schema.org/draft/2020-12/meta/validation#/properties/type"
-                },
-                "format": { "$ref": "#/definitions/formats" },
-                "enum": {
-                  "type": "array"
+              "allOf": [
+                { "$ref": "#/definitions/schemaTerm" },
+                { "$ref": "#/definitions/generalTerm" },
+                { "$ref": "#/definitions/nameValueTerm" },
+                {
+                  "type": "object",
+                  "properties": {
+                    "format": { "$ref": "#/definitions/formats" }
+                  },
+                  "required": ["format"]
                 }
-              },
-              "required": [
-                "name",
-                "display_name",
-                "description",
-                "type",
-                "format"
               ],
-              "additionalProperties": false
+              "unevaluatedProperties": false
             }
           },
           "additionalProperties": false
@@ -203,30 +148,18 @@
         "enums": {
           "type": "object",
           "patternProperties": {
-            "^[a-zA-Z0-9_-]+$": {
-              "type": "object",
-              "properties": {
-                "type": {
-                  "$ref": "http://json-schema.org/draft/2020-12/meta/validation#/properties/type"
-                },
-                "enum": {
-                  "type": "array"
-                },
-                "value": {
-                  "type": "string"
-                },
-                "display_name": {
-                  "type": "string"
-                },
-                "description": {
-                  "type": "string"
-                },
-                "tags": {
-                  "type": "array"
-                }
-              },
-              "additionalProperties": false
-            }
+            "^[a-zA-Z0-9][a-zA-Z0-9_-]*$": {
+              "allOf": [
+                { "$ref": "#/definitions/generalTerm" },
+                { "$ref": "#/definitions/valueTerm" },
+                { "properties": { "tags": { "type": "array" } } }
+              ]
+            },
+            "^_[a-zA-Z0-9_-]+$": {
+              "$ref": "http://json-schema.org/draft/2020-12/schema#",
+              "required": ["type", "enum"]
+            },
+            "unevaluatedProperties": false
           },
           "additionalProperties": false
         },
@@ -234,20 +167,11 @@
           "type": "object",
           "patternProperties": {
             "^[a-zA-Z0-9_]+$": {
-              "type": "object",
-              "properties": {
-                "value": {
-                  "type": "string"
-                },
-                "display_name": {
-                  "type": "string"
-                },
-                "description": {
-                  "type": "string"
-                }
-              },
-              "required": ["display_name", "description", "value"],
-              "additionalProperties": false
+              "allOf": [
+                { "$ref": "#/definitions/generalTerm" },
+                { "$ref": "#/definitions/valueTerm" }
+              ],
+              "unevaluatedProperties": false
             }
           },
           "additionalProperties": false
@@ -256,20 +180,14 @@
           "type": "object",
           "patternProperties": {
             "^[a-zA-Z0-9_]+$": {
-              "type": "object",
-              "properties": {
-                "display_name": {
-                  "type": "string"
-                },
-                "file_type": {
-                  "type": "string"
-                },
-                "description": {
-                  "type": "string"
+              "allOf": [
+                { "$ref": "#/definitions/generalTerm" },
+                {
+                  "properties": { "file_type": { "type": "string" } },
+                  "required": ["file_type"]
                 }
-              },
-              "required": ["display_name", "file_type", "description"],
-              "additionalProperties": false
+              ],
+              "unevaluatedProperties": false
             }
           },
           "additionalProperties": false
@@ -278,41 +196,38 @@
           "type": "object",
           "propertyNames": { "$ref": "#/definitions/formats" },
           "additionalProperties": {
-            "type": "object",
-            "properties": {
-              "display_name": {
-                "type": "string"
-              },
-              "description": {
-                "type": "string"
-              },
-              "pattern": {
-                "format": "regex"
+            "allOf": [
+              { "$ref": "#/definitions/generalTerm" },
+              {
+                "properties": {
+                  "pattern": {
+                    "$ref": "http://json-schema.org/draft/2020-12/meta/validation#/properties/pattern"
+                  }
+                },
+                "required": ["pattern"]
               }
-            },
-            "required": ["display_name", "description", "pattern"]
+            ],
+            "unevaluatedProperties": false
           }
         },
         "metadata": {
           "type": "object",
           "patternProperties": {
             "^[a-zA-Z0-9_]+$": {
-              "type": "object",
-              "properties": {
-                "name": {
-                  "type": "string"
-                },
-                "display_name": {
-                  "type": "string"
-                },
-                "description": {
-                  "type": "string"
-                },
-                "type": {
-                  "$ref": "http://json-schema.org/draft/2020-12/meta/validation#/properties/type"
+              "allOf": [
+                { "$ref": "#/definitions/schemaTerm" },
+                { "$ref": "#/definitions/generalTerm" },
+                { "$ref": "#/definitions/nameValueTerm" },
+                {
+                  "properties": {
+                    "recommended": {
+                      "$ref": "http://json-schema.org/draft/2020-12/meta/validation#/properties/required"
+                    },
+                    "unit": { "type": "string" }
+                  }
                 }
-              },
-              "required": ["name", "display_name", "description"]
+              ],
+              "unevaluatedProperties": false
             }
           },
           "additionalProperties": false
@@ -321,17 +236,8 @@
           "type": "object",
           "patternProperties": {
             "^[a-z]+$": {
-              "type": "object",
-              "properties": {
-                "display_name": {
-                  "type": "string"
-                },
-                "description": {
-                  "type": "string"
-                }
-              },
-              "required": ["display_name", "description"],
-              "additionalProperties": false
+              "$ref": "#/definitions/generalTerm",
+              "unevaluatedProperties": false
             }
           },
           "additionalProperties": false
@@ -340,19 +246,21 @@
           "type": "object",
           "patternProperties": {
             "^[a-zA-Z0-9_]+$": {
-              "type": "object",
-              "properties": {
-                "value": {
-                  "type": "string"
-                },
-                "display_name": {
-                  "type": "string"
-                },
-                "description": {
-                  "type": "string"
+              "allOf": [
+                { "$ref": "#/definitions/generalTerm" },
+                { "$ref": "#/definitions/valueTerm" },
+                {
+                  "properties": {
+                    "unit": { "type": "string" },
+                    "anyOf": {
+                      "$ref": "http://json-schema.org/draft/2020-12/meta/applicator#/properties/anyOf"
+                    },
+                    "maxValue": { "type": "number" },
+                    "minValue": { "type": "number" }
+                  }
                 }
-              },
-              "required": ["value", "display_name", "description"]
+              ],
+              "unevaluatedProperties": false
             },
             "additionalProperties": false
           }
@@ -622,6 +530,28 @@
         "uri"
       ]
     },
+    "generalTerm": {
+      "type": "object",
+      "properties": {
+        "display_name": { "type": "string" },
+        "description": { "type": "string" }
+      },
+      "required": ["display_name", "description"]
+    },
+    "schemaTerm": {
+      "$ref": "http://json-schema.org/draft/2020-12/schema#",
+      "anyOf": [{ "required": ["type"] }, { "required": ["anyOf"] }]
+    },
+    "nameValueTerm": {
+      "type": "object",
+      "properties": { "name": { "type": "string" } },
+      "required": ["name"]
+    },
+    "valueTerm": {
+      "type": "object",
+      "properties": { "value": { "type": "string" } },
+      "required": ["value"]
+    },
     "entities": {
       "type": "object",
       "patternProperties": {