What does instantiate mean in Java?

Instantiate means create an instance of a class.

So if a class is a template of a part, then instances are different parts created from this template.

Instances are also called objects in Java.

class Person {

  String name;

  Person(String name) {
    this.name = name;

// We have instantiated 2 objects of class Person.
// Jane and Bill are instances of Person.
Person jane = new Person("Jane");
Person bill = new Person("Bill");