Barclay m
Scottish, English, and Irish: generally a transferred use of the Scottish surname, which was taken to Scotland in the 12th century by Walter de Berchelai, who became chamberlain of Scotland in 1165. His name is almost certainly derived from Berkeley in Gloucestershire, which is named with the Old English elements beorc birch tree + lēah wood or clearing. His descendants became one of the most powerful families in Scotland, and the transferred use as a given name probably originated in Scotland with reference to this family. In Ireland it has been pressed into service as an Anglicized form of PARTHALÁN (SEE Parthalán).
First names dictionary. 2012.