Objects in JavaScript can be thought of as maps between keys and values. The delete operator is used to remove these keys.

var obj = {
  myProperty: 1    
console.log(obj.hasOwnProperty('myProperty')) // true
delete obj.myProperty
console.log(obj.hasOwnProperty('myProperty')) // false

Or, you can use object destructuring, an ECMAScript 6 feature, it's as simple as:

let myObject = {
  "item1": "value",
  "item2": "value",
  "item3": "value"
({ item1, ...myObject } = myObject);