The story
- Irish · derived fromÓ Cearnacháin“descendant of Cearnachán”
- English todayCarnahan
Reduced Anglicized form of Irish Ó Cearnacháin (“descendant of Cearnachán”), a personal name from cearnach (“victorious”) + -án (“diminutive suffix”).
Etymology from Wiktionary, CC BY-SA 4.0.