Added 10 October 2026 semiannual adjective Categories: Describing WordsRare Words adjective ! Definition from WordNet 3.1, Princeton University. More about semiannual at Wordnik → Where our words come from → Occurring or payable twice each year. Related Words: biannualbiyearlyhalf-yearlybi-annualsemi-annualtwice-yearlybimestrialsemestralbimonthlysemimonthlybiennialbiennary Back to today's word