from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Happening once every 20 years.
- adj. Existing or lasting for 20 years.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Occurring every twenty years.
- adj. Lasting twenty years.
from the GNU version of the Collaborative International Dictionary of English
- adj. Lasting or comprising twenty years.
- adj. Happening once in twenty years.
from The Century Dictionary and Cyclopedia
- Lasting or continuing twenty years: as, a vicennial charter or license.
- Happening once in twenty years: as, a vicennial commemoration.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. occurring once every 20 years
From Late Latin vīcennium, period of twenty years : Latin vīciēns, twenty times (from vīgintī, twenty; see vicenary) + Latin annus, year; see at- in Indo-European roots.(American Heritage® Dictionary of the English Language, Fourth Edition)