Added 10 October 2026 five-eighths noun Categories: Obscure Words noun ! Definition from Wiktionary (CC BY-SA). More about five-eighths at Wordnik → Where our words come from → Five of eighth equal parts (5/8, ⅝, 0.625). plural of five-eighth Related Words: seven-eighthsthree-eighthsfour-fifthsfive-sixthsone-fifthtwo-fifthseighthone-eighth Back to today's word