Overextension

Overextension occurs when a categorical term (a word used to describe a group of things) is used in language to represent more categories than it actually does. This happens in particular with very young children. An example is when a child refers to all animals as 'doggie' or refers to a lion as a 'kitty.' The child is overextending the definition of dog to encompass all animals and using the term 'kitty' for all felines instead of just house cats.