Create new object dynamically

Is there a way of adding an object without having to declare a const?

function Car (make, color) {
    this.make = make,
    this.color = color,  
    this.greet = function () {
        console.log(`The make is ${this.make} and color is ${this.color}`);
  };
}

const newObject = "Toyota"

const ford = new Car("Ford", "blue")
ford.greet();``

const vauxhall = new Car("Vauxhall", "green")
vauxhall.greet();

I thought I may be able to have:

const newObject = "Toyota"

Then add Toyota in place of ford or vauxhall.