from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Not derived; basic: an underived postulate.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. not derived, not related.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. not derived; primary or simple
un- + derived (Wiktionary)