Dictionary of Root Words: Greek and Latin Roots

What are “Root Words”?

A root or root word is a word that is used to form another word. It is also called a base word. A root does not have a prefix (a letter or group of letters added to the beginning of a word) or a suffix (a letter or group of letters added to the end of a word).
The root is the primary lexical unit of a word, and of a word family.

For example, pure is a root. By adding prefixes and suffixes, the following words could be made:
impure, purity, pureness

Similarly, play and move...