the.com/centenary

A birthday so good you only get to brag about it once a century.

means A hundredth anniversary, or the celebration marking it.

from Built in the 1800s from Latin 'centenarius', meaning 'containing a hundred', itself rooted in 'centum', the Latin word for 'hundred' — the same root that gives us 'century' and 'cent'.

origin
from Latin centum, meaning one hundred
usage
Brits say centenary, Americans say centennial
related
bicentenary doubles it, sesquicentennial splits the difference
rarity
most institutions never live long enough to have one
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