diff --git a/knex/index.d.ts b/knex/index.d.ts
index 5196f47eb0..3e7dc595f4 100644
--- a/knex/index.d.ts
+++ b/knex/index.d.ts
@@ -2,6 +2,7 @@
 // Project: https://github.com/tgriesser/knex
 // Definitions by: Qubo <https://github.com/tkQubo>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
+// TypeScript Version: 2.1
 
 /// <reference types="bluebird" />
 /// <reference types="node" />
@@ -383,6 +384,7 @@ declare namespace Knex {
         dropForeign(columnNames: string[], foreignKeyName?: string): TableBuilder;
         dropUnique(columnNames: string[], indexName?: string): TableBuilder;
         dropPrimary(constraintName?: string): TableBuilder;
+        dropIndex(columnNames: string[], indexName?: string): TableBuilder;
     }
 
     interface CreateTableBuilder extends TableBuilder {