In JavaScript, an object literal is a way to create an object by directly specifying its properties and values within curly braces {}. It's a simple and concise syntax for creating objects without needing to define a separate constructor function.

Here's an example of an object literal:

var person = {
  name: "John",
  age: 30,
  city: "New York"
};

In this example, person is an object created using an object literal. It has three properties: name, age, and city, each with their respective values.

But, if you want to create an object using a constructor function in JavaScript, you can define a function and then use the new keyword to instantiate an object from that function. Here's an example:

// Constructor function
function Person(name, age, city) {
  this.name = name;
  this.age = age;
  this.city = city;
}

// Creating an object using the constructor
var person1 = new Person("John", 30, "New York");