Ó Faoilleacháin
Ó FAOILLEACHÁIN—I—O Whyleghane, O Philaghane, O Feylaghan, Wheleghan, Wheelahan, Whelahan, Whelehan, (Whelan, Phelan); 'descendant of Faoilleachán' (diminutive of faoilleach, joyful; perhaps born in carnival time, the month of rejoicing, from middle of January to middle of February); an old Westmeath surname. Ó hAoilleacháin (which see) is a Munster variant.
Alphabetical Index to Irish Surnames