diff --git a/static/js/directives/ui/typeahead/typeahead.directive.ts b/static/js/directives/ui/typeahead/typeahead.directive.ts
index d49b6de9c..8b494636c 100644
--- a/static/js/directives/ui/typeahead/typeahead.directive.ts
+++ b/static/js/directives/ui/typeahead/typeahead.directive.ts
@@ -19,7 +19,7 @@ export class TypeaheadDirective implements AfterContentInit {
   @Output('taEntered') entered = new EventEmitter<any>();
 
   private itemSelected: boolean = false;
-  private existingTimer: Promise = null;
+  private existingTimer: ng.IPromise<void> = null;
 
   constructor(@Inject('$element') private $element: ng.IAugmentedJQuery,
               @Inject('$compile') private $compile: ng.ICompileService,