from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Not open to argument or further discussion: the plain, unarguable facts.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Not arguable; that cannot be reasonably argued against.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. against which no argument can be made
un- + arguable (Wiktionary)