What is the term used to describe the process involved when a child uses one word like "ball" to refer to an "apple", an "egg", a "grape" and a "ball"?

The term is called overextension which is used to describe a situation whereby a child overextends or generalizes the meaning of words when referring to other things or objects that look almost similar in shape, appearance, sound, movement, etc. For example, a child may use the word "cat" to refer to any animal.