octogenarian UK /ˌɒktəd͡ʒɪˈnɛəɹɪən/US /ˌɑktəd͡ʒɪˈnɛɹiən/adjective 1noun 1forms 1 adjective1 •Of or related to eightysomethings. noun1 •Synonym of eightysomething: a person between 80 and 89 years old.Finsbury Park station, one of the most important L.N.E.R. suburban junctions, is now an octogenarian. — 1941 formsoctogenarians
