diff --git a/node/node-0.10.d.ts b/node/node-0.10.d.ts
index 5192f33457..b277749fb2 100644
--- a/node/node-0.10.d.ts
+++ b/node/node-0.10.d.ts
@@ -99,6 +99,7 @@ declare namespace NodeJS {
 
     export interface ReadableStream extends EventEmitter {
         readable: boolean;
+        isTTY?: boolean;
         read(size?: number): any;
         setEncoding(encoding: string): void;
         pause(): void;
@@ -112,6 +113,7 @@ declare namespace NodeJS {
 
     export interface WritableStream extends EventEmitter {
         writable: boolean;
+        isTTY?: boolean;
         write(buffer: Buffer, cb?: Function): boolean;
         write(str: string, cb?: Function): boolean;
         write(str: string, encoding?: string, cb?: Function): boolean;
diff --git a/node/node-0.11.d.ts b/node/node-0.11.d.ts
index d153a11f7e..22a94069a6 100644
--- a/node/node-0.11.d.ts
+++ b/node/node-0.11.d.ts
@@ -99,6 +99,7 @@ declare namespace NodeJS {
 
     export interface ReadableStream extends EventEmitter {
         readable: boolean;
+        isTTY?: boolean;
         read(size?: number): any;
         setEncoding(encoding: string): void;
         pause(): void;
@@ -112,6 +113,7 @@ declare namespace NodeJS {
 
     export interface WritableStream extends EventEmitter {
         writable: boolean;
+        isTTY?: boolean;
         write(buffer: Buffer, cb?: Function): boolean;
         write(str: string, cb?: Function): boolean;
         write(str: string, encoding?: string, cb?: Function): boolean;
diff --git a/node/node-0.12.d.ts b/node/node-0.12.d.ts
index 511ecc6e6a..a31c58363e 100644
--- a/node/node-0.12.d.ts
+++ b/node/node-0.12.d.ts
@@ -180,6 +180,7 @@ declare namespace NodeJS {
 
     export interface ReadableStream extends EventEmitter {
         readable: boolean;
+        isTTY?: boolean;
         read(size?: number): string|Buffer;
         setEncoding(encoding: string): void;
         pause(): void;
@@ -193,6 +194,7 @@ declare namespace NodeJS {
 
     export interface WritableStream extends EventEmitter {
         writable: boolean;
+        isTTY?: boolean;
         write(buffer: Buffer|string, cb?: Function): boolean;
         write(str: string, encoding?: string, cb?: Function): boolean;
         end(): void;
diff --git a/node/node-0.8.8.d.ts b/node/node-0.8.8.d.ts
index 7bf214b781..fa03e382ac 100644
--- a/node/node-0.8.8.d.ts
+++ b/node/node-0.8.8.d.ts
@@ -89,6 +89,7 @@ interface EventEmitter {
 
 interface WritableStream extends EventEmitter {
     writable: boolean;
+    isTTY?: boolean;
     write(str: string, encoding?: string, fd?: string): boolean;
     write(buffer: Buffer): boolean;
     end(): void;
@@ -100,6 +101,7 @@ interface WritableStream extends EventEmitter {
 
 interface ReadableStream extends EventEmitter {
     readable: boolean;
+    isTTY?: boolean;
     setEncoding(encoding: string): void;
     pause(): void;
     resume(): void;
diff --git a/node/node-4.d.ts b/node/node-4.d.ts
index bd6196d17c..cab592740e 100644
--- a/node/node-4.d.ts
+++ b/node/node-4.d.ts
@@ -232,6 +232,7 @@ declare namespace NodeJS {
 
     export interface ReadableStream extends EventEmitter {
         readable: boolean;
+        isTTY?: boolean;
         read(size?: number): string|Buffer;
         setEncoding(encoding: string): void;
         pause(): void;
@@ -245,6 +246,7 @@ declare namespace NodeJS {
 
     export interface WritableStream extends EventEmitter {
         writable: boolean;
+        isTTY?: boolean;
         write(buffer: Buffer|string, cb?: Function): boolean;
         write(str: string, encoding?: string, cb?: Function): boolean;
         end(): void;
diff --git a/node/node.d.ts b/node/node.d.ts
index cbdc1d30db..97e8922cc5 100644
--- a/node/node.d.ts
+++ b/node/node.d.ts
@@ -259,6 +259,7 @@ declare namespace NodeJS {
 
     export interface ReadableStream extends EventEmitter {
         readable: boolean;
+        isTTY?: boolean;
         read(size?: number): string | Buffer;
         setEncoding(encoding: string): void;
         pause(): ReadableStream;
@@ -272,6 +273,7 @@ declare namespace NodeJS {
 
     export interface WritableStream extends EventEmitter {
         writable: boolean;
+        isTTY?: boolean;
         write(buffer: Buffer | string, cb?: Function): boolean;
         write(str: string, encoding?: string, cb?: Function): boolean;
         end(): void;