According the the 1920 notes of my Grandfather, A.J.(Abner John II) Adair. " It was in the 14th century when Robert Fitzgerald de Adare fought the duel with the White Knight, a kinsman, at the ford ( the ford on the Maigue River from which the name Adare or Adair comes). After slaying his antagonist in combate, he removed himself to Galloway Scotland where he wrote himselp simply as Robert Adair. My Grandfather seems to have gotten his information from the writings of Ruby Haskins Ellis. Hope this helps. I am very interested Robert Fitzgerald de Adare also.