diff --git a/src/types/duid.ts b/src/types/duid.ts
deleted file mode 100644
index 53747e42..00000000
--- a/src/types/duid.ts
+++ /dev/null
@@ -1,11 +0,0 @@
-/**
- * @file Type Definitions - DUID
- * @module tutils/types/DUID
- */
-
-/**
- * Default field used as unique identifier for documents.
- */
-type DUID = 'id'
-
-export { type DUID as default }
diff --git a/src/types/index.ts b/src/types/index.ts
index c5b5451a..c4b09150 100644
--- a/src/types/index.ts
+++ b/src/types/index.ts
@@ -11,7 +11,6 @@ export type { default as Constructor } from './constructor'
 export type { default as ContinuousValue } from './continuous-value'
 export type { default as DeepPartial } from './deep-partial'
 export type { default as DeepPick } from './deep-pick'
-export type { default as DUID } from './duid'
 export type { default as EmptyString } from './empty-string'
 export type { default as EmptyValue } from './empty-value'
 export type { default as FIXME } from './fixme'