diff --git a/src/lib/expansion/expansion-panel.ts b/src/lib/expansion/expansion-panel.ts
index 2b3631e2f343..fd1e4d9caee9 100644
--- a/src/lib/expansion/expansion-panel.ts
+++ b/src/lib/expansion/expansion-panel.ts
@@ -45,7 +45,7 @@ let uniqueId = 0;
  * `<mat-expansion-panel>`
  *
  * This component can be used as a single element to show expandable content, or as one of
- * multiple children of an element with the MdAccordion directive attached.
+ * multiple children of an element with the MatAccordion directive attached.
  */
 @Component({
   moduleId: module.id,