derivational Definition

1. The act of deriving or the state or process of being derived.
2. The source or origin (especially of a word).

Thesaurus: origin, source, root, beginning, foundation, basis, extraction, descent, ancestry, genealogy, etymology.
3a. grammar.
The process of forming a word by adding one or more affixes to another word;
3b. grammar.
A word formed in this way.