diff --git a/jasmine-data_driven_tests/jasmine-data_driven_tests.d.ts b/jasmine-data_driven_tests/jasmine-data_driven_tests.d.ts
index c0936872b0..912720e7f3 100644
--- a/jasmine-data_driven_tests/jasmine-data_driven_tests.d.ts
+++ b/jasmine-data_driven_tests/jasmine-data_driven_tests.d.ts
@@ -3,5 +3,5 @@
 // Definitions by: Anthony MacKinnon <https://github.com/AnthonyMacKinnon>
 // Definitions: https://github.com/borisyankov/DefinitelyTyped
 
-declare function all(description: string, dataset: any[], specDefinitions: (...args: any[]) => void): void;
-declare function xall(description: string, dataset: any[], specDefinitions: (...args: any[]) => void): void;
\ No newline at end of file
+declare function all(description: string, dataset: any[], assertion: (...args: any[]) => void): void;
+declare function xall(description: string, dataset: any[], assertion: (...args: any[]) => void): void;
\ No newline at end of file