diff --git a/core/server/services/settings/validate.js b/core/server/services/settings/validate.js
index 4bce0e9f95..c67d4c5cbc 100644
--- a/core/server/services/settings/validate.js
+++ b/core/server/services/settings/validate.js
@@ -302,6 +302,7 @@ _private.validateCollections = function validateCollections(collections) {
 };
 
 _private.validateTaxonomies = function validateTaxonomies(taxonomies) {
+    const validRoutingTypeObjectKeys = Object.keys(RESOURCE_CONFIG.TAXONOMIES);
     _.each(taxonomies, (routingTypeObject, routingTypeObjectKey) => {
         if (!routingTypeObject) {
             throw new common.errors.ValidationError({
@@ -313,6 +314,15 @@ _private.validateTaxonomies = function validateTaxonomies(taxonomies) {
             });
         }
 
+        if (!validRoutingTypeObjectKeys.includes(routingTypeObjectKey)) {
+            throw new common.errors.ValidationError({
+                message: common.i18n.t('errors.services.settings.yaml.validate', {
+                    at: routingTypeObjectKey,
+                    reason: 'Unknown taxonomy.'
+                })
+            });
+        }
+
         // CASE: we hard-require trailing slashes for the taxonomie permalink route
         if (!routingTypeObject.match(/\/$/)) {
             throw new common.errors.ValidationError({
diff --git a/core/test/unit/services/settings/validate_spec.js b/core/test/unit/services/settings/validate_spec.js
index 3d757c5cb6..e13b7646b9 100644
--- a/core/test/unit/services/settings/validate_spec.js
+++ b/core/test/unit/services/settings/validate_spec.js
@@ -35,7 +35,22 @@ describe('UNIT: services/settings/validate', function () {
         try {
             validate({
                 taxonomies: {
-                    tags: '/categories/:slug/'
+                    tag: '/categories/:slug/'
+                }
+            });
+        } catch (err) {
+            (err instanceof common.errors.ValidationError).should.be.true();
+            return;
+        }
+
+        throw new Error('should fail');
+    });
+
+    it('throws error when using an undefined taxonomy', function () {
+        try {
+            validate({
+                taxonomies: {
+                    sweet_baked_good: '/patisserie/{slug}'
                 }
             });
         } catch (err) {
@@ -220,7 +235,7 @@ describe('UNIT: services/settings/validate', function () {
                 }
             },
             taxonomies: {
-                tags: '/tags/{slug}/',
+                tag: '/tags/{slug}/',
                 author: '/authors/{slug}/',
             }
         });
@@ -228,7 +243,7 @@ describe('UNIT: services/settings/validate', function () {
         object.should.eql({
             routes: {},
             taxonomies: {
-                tags: '/tags/:slug/',
+                tag: '/tags/:slug/',
                 author: '/authors/:slug/'
             },
             collections: {