What is "mcphillips"

Although some historians claim the McPhillips surname is of Scottish origin, the surname is found predominantly in Ireland, in Cavan, Fermanagh and Monaghan counties. In Ulster, the McPhillips are in Gaelic MacPilib or MacPhilib. Other historians claim they are a branch of the McMahons clan of Oriel, descendants of the coarb of Clones Abbey, Philip MacMahon.