diff --git a/src/cdk/overlay/overlay.ts b/src/cdk/overlay/overlay.ts
index d29135858c2..cdaeee95a4c 100644
--- a/src/cdk/overlay/overlay.ts
+++ b/src/cdk/overlay/overlay.ts
@@ -29,7 +29,7 @@ let nextUniqueId = 0;
 
 /**
  * Service to create Overlays. Overlays are dynamically added pieces of floating UI, meant to be
- * used as a low-level building building block for other components. Dialogs, tooltips, menus,
+ * used as a low-level building block for other components. Dialogs, tooltips, menus,
  * selects, etc. can all be built using overlays. The service should primarily be used by authors
  * of re-usable components rather than developers building end-user applications.
  *