diff --git a/synonym.go b/synonym.go
new file mode 100644
index 0000000..c85ea60
--- /dev/null
+++ b/synonym.go
@@ -0,0 +1,32 @@
+//  Copyright (c) 2024 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package index
+
+type SynonymField interface {
+	Field
+	VisitSynonymDefinitions(visitor func(SynonymDefinition))
+}
+
+type SynonymFieldVisitor func(SynonymField)
+
+type SynonymDefinition interface {
+	Term() string
+	Synonyms() []string
+}
+
+type SynonymDocument interface {
+	Document
+	VisitSynonymField(visitor SynonymFieldVisitor)
+}