from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Continuing through the week: a weeklong conference.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. which lasts for a week, or approximately so
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. lasting through a week
week + -long (Wiktionary)