this.anotherValue = val;
      },
      configurable: true,
      enumerable: true,
    });
    o.value = 5;
    console.log(o.value); // undefined
    console.log(o.anotherValue); // 5
    

##  Specifications

Specification  
---  
[ ECMAScript Language Specification  
#  sec-object.prototype.__defineSetter__
](https://tc39.es/ecma262/multipage/additional-ecmascript-features-for-web-
browsers.html#sec-object.prototype.__defineSetter__)  
  
##  Browser compatibility

BCD tables only load in the browser  with JavaScript enabled. Enable
JavaScript to view data.

##  See also

  * [ Polyfill of ` Object.prototype.__defineSetter__ ` in ` core-js ` ](https://github.com/zloirock/core-js#ecmascript-object)
  * [ ` Object.prototype.__defineGetter__() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/__defineGetter__)
  * [ ` set ` ](/en-US/docs/Web/JavaScript/Reference/Functions/set)
  * [ ` Object.defineProperty() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty)
  * [ ` Object.prototype.__lookupGetter__() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/__lookupGetter__)
  * [ ` Object.prototype.__lookupSetter__() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/__lookupSetter__)
  * [ JS Guide: Defining Getters and Setters ](/en-US/docs/Web/JavaScript/Guide/Working_with_objects#defining_getters_and_setters)
  * [ Firefox bug 647423 ](https://bugzil.la/647423)

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