Regarding Facilities and Areas and the Status of United States Armed Forces in Japan, signed at Tokyo on January 25, 2008, Noting situations involving both countries,
Familiarity information: BICENTENNIAL used as a noun is very rare. â¢ BICENTENNIAL (adjective). The adjective BICENTENNIAL has 1 sense: 1. of or relating to or completing a period of 200 years. Familiarity information: BICENTENNIAL used as an adjective is very rare.
Confidence votes 7.7K. There is disagreement on whether there even exists a proper, unambiguous term for every four months.. Many use triannual for the purpose. There is some logic to this, since biannual means twice yearly, whereas biennial means every two years, and triennial means every three years.