from Wiktionary, Creative Commons Attribution/Share-Alike License
- adv. As part of a centennial.
from the GNU version of the Collaborative International Dictionary of English
- adv. Once in a hundred years.
from The Century Dictionary and Cyclopedia
- Once in every hundred years: as, to celebrate an event centennially.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adv. every hundred years; once in a century
centennial + -ly (Wiktionary)