Scottish and Irish: 1. Anglicized form of Gaelic Mac Eoghain ‘son of Eoghan’, a widespread and ancient personal name, possibly derived from eo ‘yew’, meaning ‘born of yew’. It was Latinized as Eugenius (see Eugene), and was also regarded as a Gaelic form of John. This was the name of one of the two sons of Niall of the Nine Hostages; the other was Conall. 2. Anglicized form of Mac Eathain ‘son of Eathan’, a Scottish Gaelic form of Latin Johannes (see John). John was taken into Irish as Eoin at first; Seán is a later form. In later Irish, as in the surnames, the personal names Eoghan and Eoin were often confused.