Added 9 October 2026 half-hour noun Categories: TimeObscure Words In Latin: sēmihōra Wiktionary noun ! Definition from WordNet 3.1, Princeton University. More about half-hour at Wordnik → Where our words come from → A half of an hour. Origin From half- + hour. From Wiktionary, via Kaikki.org (CC BY-SA) Related Words: hourone-halfhalfminhalfmonthquarter-hourhalf-timequarterhalf-century Back to today's word