Argyll, archaically Argyle (Earra-Ghàidheal in modern Gaelic), is a region of western Scotland corresponding with most of the part of ancient Dál Riata that was located on the island of Great Britain, and can be used to mean the entire western seaboard between the Mull of Kintyre and Cape Wrath. The early thirteenth century author of De Situ Albanie explains that "the name Arregathel means margin of the Scots or Irish, because all Scots and Irish are generally called Gattheli [=Gaels], from their ancient warleader known as Gaithelglas." Argyll was a medieval Bishopric too, with its cathedral at Lismore, as well as an early modern Earldom and Duchy, the Duchy of Argyll.
Today Argyll is a registration county for property.