Recorded in several spellings including MacCrossan, McCrossan, Crossan, Crosan, Crosen, Croson, Crossen, Crosson and others, this is an Irish surname. It is a developed form of the pre 10th century Gaelic Mac an Chrosain, meaning 'The son of the reciter of verse'. Originally the surname may have denoted one who carried a cross in religious processions of the Christian Church. There are two distinct septs of the MacCrossan's, the most numerous being in North Ulster, and mainly in County Tyrone and County Derry. In Tyrone the prefix "mac" has been retained, but in County Derry like much of the rest of Ireland, it has been dropped. The other sept were from Mid Leinster, and the village of Ballymacrossan, County Laois is named after this sept. These MacCrossans however, have long disguised their name under the English form of Crosby or Crosbie. The Chancery Rolls of 1550 record the pardon of one Owen Oge MacCrossan of Ballymacroosan, County Laois. The first recorded spelling of the family name is shown to be that of Henry MacCrossan. This was dated circa 1350, when he became the bishop of Raphoe. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.