| Semiannual (a.) Recurring at intervals of six months; appearing twice a year. Thesaurus Entries annual, biannual, biennial, bimonthly, biweekly, catamenial, centenary, centennial, daily, decennial, diurnal, fortnightly, hebdomadal, hourly, menstrual, momentary, momently, monthly, quarterly, quotidian, secular, semestral, semimonthly, semiweekly, semiyearly, tertian, triennial, weekly, yearly |