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adj. Happening every two years. See Usage Note at bi-1.

adj. Happening twice a year; semiyearly.

ad. Every two years.

ad. Twice a year; semiyearly.

adj. Occurring every two years; biennial

adj. Occurring twice per year; biannual

ad. Every two years; biennially

ad. Twice per year; biannually

ad. every two years

adj. occurring or payable twice each year

ad. twice a year

adj. occurring every second year

"There's still the biyearly Northwestern minefield and the quadrennial recruiting junket to Hawaii to deal with, and that's beyond the fact the Beat Michigan Club isn't exactly exclusive these last two years."

periodical    periodic