diff --git a/lib/aggregation_cursor.js b/lib/aggregation_cursor.js
index aa9d207e7cf..bb12fdb1471 100644
--- a/lib/aggregation_cursor.js
+++ b/lib/aggregation_cursor.js
@@ -202,7 +202,7 @@ class AggregationCursor extends Cursor {
   /**
    * Add a unwind stage to the aggregation pipeline
    * @method
-   * @param {number} field The unwind field name.
+   * @param {(string|object)} field The unwind field name or stage document.
    * @return {AggregationCursor}
    */
   unwind(field) {