Which keyword is used to define a constructor in Java?

In Java, a constructor is defined by using the same name as the class and does not have a return type, not even void. Constructors are typically declared as public to allow for the creation of objects from outside the class. This visibility modifier gives access to the constructor, enabling instances of the class to be created from other classes.

The keyword "public" indicates that the constructor can be accessed from any other class, ensuring that objects can be instantiated without any accessibility issues. While "new" is used when creating an object (for example, new ClassName()), it is not the keyword that directly defines the constructor itself. The keywords "define" and "create" simply do not pertain to Java's syntax for constructors.

Understanding the role of constructors and their visibility modifiers like "public" is fundamental in object-oriented programming, as it influences how classes and objects interact.