diff --git a/d3/d3.d.ts b/d3/d3.d.ts
index e6e1941c94..14e2e26e5b 100644
--- a/d3/d3.d.ts
+++ b/d3/d3.d.ts
@@ -2535,6 +2535,7 @@ declare module d3 {
 
             tickFormat(): (t: any) => string;
             tickFormat(format: (t: any) => string): Axis;
+            tickFormat(format:string): Axis;
         }
 
         export function brush(): Brush<any>;