a small add-on that usually changes some elements of the game, like adding a new weapon or making the player's head larger
method that allows one to modify (i.e. mutate) part of the object. For example, a setRadius() method is a mutator, as it allows you to set the radius of a Circle object.
An accessing method that sets a new value for a variable. also accessor.
A Java method that changes the state of an object is called a mutator. Mutators typically do not return a result (are declared to return void), although some mutators both change state and return a result (e.g., nextToken in StringTokenizer). Mutators just change state, without looking at current values, are often call "setters", and their names often start with set. See accessor.