Prefix - Definition, Meaning & Examples

Prefix is a morpheme that is added to the beginning of a word to modify its meaning. Prefixes can change the meaning of a word by adding a new concept or by negating the original meaning. For example, the prefix "un-" can be added to the word "happy" to create the word "unhappy", which means the opposite of happy. Prefixes are a common feature of many languages and they can be used to create new words, expand vocabulary, and make language more expressive.