diff --git a/src/type/definition.js b/src/type/definition.js
index c6d8945852..1ae929a287 100644
--- a/src/type/definition.js
+++ b/src/type/definition.js
@@ -917,7 +917,7 @@ export type InputObjectConfig = {
   description?: ?string;
 }
 
-type InputObjectConfigFieldMapThunk = () => InputObjectConfigFieldMap;
+export type InputObjectConfigFieldMapThunk = () => InputObjectConfigFieldMap;
 
 export type InputObjectFieldConfig = {
   type: GraphQLInputType;