Synonyms of 'biannual'

annual, biennial, bimonthly, biweekly, centenary, centennial, daily, decennial, diurnal, fortnightly, hebdomadal, hourly, menstrual, momentary, momently, monthly, quarterly, quotidian, secular, semiannual, semimonthly, semiweekly, tertian, triennial, weekly, yearly