centennially

from WordNet (r) 3.0 (2006)
centennially
    adv 1: every hundred years; once in a century; "the birthday of
           this city is being celebrated centennially"
from The Collaborative International Dictionary of English v.0.48
Centennially \Cen*ten"ni*al*ly\, adv.
   Once in a hundred years.
   [1913 Webster]
antiflux / dictionary / centennially
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