From Longman Dictionary of Contemporary Englishbicentennialbi‧cen‧ten‧ni‧al /ˌbaɪsenˈteniəl/ noun [countable] American EnglishTMC the day or year exactly 200 years after an important event the bicentennial of the Declaration of Independence —bicentennial adjective bicentennial celebrations
Examples from the Corpus
bicentennial• But did you know that this mechanical wonder is celebrating its bicentennial? 