Ó Eachthighearna
Ó EACHTHIGHEARNA, Ó EACHTHIGHEIRN, Ó EICHTHIGHEIRN—I—O Aghierny, O Aghierin, Ahearne, Aherne, Ahearn, Aheran, Aheron, Ahern, &c.; 'descendant of Eachthighearna' (horse-lord); the name of a Dalcassian family who were lords of Ui Cearnaigh, in the neighbourhood of Six-mile-bridge, until about the year 1318, when they were driven out by the MacNamaras and dispersed through Munster. The name is now common in Limerick and Cork. Also Ó hEachthigheirn, which see.
Alphabetical Index to Irish Surnames