Recorded in an amazing number of spellings, some of which appear to bear little relationship to each other, this is a confused Irish surname of great antiquity. The spellings include McAreevy, McGreavy, McGreevy, McGrievy, McCrevy, McCreevy, McIlrea, McRavey, O' Reavey, Creevy, Kilrea, Ravey, Reavey, Revey, Reevey, Revie, and possibly others. Although in the 21st century almost entirely found in the north of Ireland, it originates from the pre 10th century Gaelic Mag Riabhach or sometimes O' Riabhach, meaning 'The son (or male descendant) of the grey one', and was popular throughout the island of Ireland. As to why somebody should be referred to as the grey one is unclear but is probably a reference to a member of a religious order, a friar perhaps as they wore grey. One branch of the clan were the lords of Moylurg in County Roscommon through to the 17th century. It is said that in the medieval period they were subdued by the MacDermots, however this subdication must have been largely by agreement, as the clan continued in its original name and homeland until at least Elizabethan times. It would seem that by the time of Petty's census of Ireland in 1659, the spelling at least in County Westmeath had become Crevy, McCrevy, McCreevy and McGreavy. In County Sligo to where members of the clan seem to have emigrated in the 18th century, the name largely changed in spelling to Kilrea and MacIlrea! The famous International Genealogical Index for 1992 lists the main surname spellings as M'Greevy, although we can find no reason for this assumption. Examples of recordings from surviving church records include James McCreavy at Dublin on April 19th 1777 when he married Anne Richardson, whilst Samuel McRavie was a baptism witness at Larne, County Antrim, on December 2nd 1864, Hugh McGreavy was a baptism witness at Ballyard, County Down, on September 11th 1865, and Richard McGreevy at Doneghadee, County Down, on September 27th 1865.