The name Adair originates in Renfrewshire when Thomas Edzear had a charter of the lands of Kildonan in the Rynes of Galloway from Robert I.
Thomas was likely descended from Edgar son of Duvenald, a leader at the Battle of the Standard. The name ‘Edzear’ is found in a charter of 1625 where both forms of the name (Adair and Edzear) are used.
Robert I also granted land in Dumfries to Richard dictus Edger.
Today the name Adair is most commonly found in Renfrewshire.