Clan Adair are a Scottish clan or family who do not have a chief recognised by the Lyon King of Arms. They are therefore considered to be an armigerous clan.
The exact origin of this name is disputed. It is a Gaelic name. <ref>George Way of Plean and Romilly Squire, Scottish Clan and Family Encyclopedia, 348</ref> According to Way of Plean and Squire it is a variation of the name 'Edzaer' and the first holder of the name is said to have been a son of Duvenald, who fought at the Battle of the Standard in 1138. Doward states that it has an Irish origin, from O'Daire. <ref> David Doward, Dictionary of Scottish Surnames, 348</ref>
During the Medieval period the name is associated with Galloway. An Adair held the lands of Kildonan from a charter issued by King Robert the Bruce. <ref>Plean, Squire, Encyclopedia, 348</ref> Sir Andrew Agnew, an aristocratic scholar of the area, used his family charters to assert that the names 'Edzaer' and 'Adair' were interchangable. <ref>Plean, Squire, Encyclopedia, 348</ref> During the era of the Elizabethan and Jacobean plantations of Ulster many of the Galloway Adairs emmigrated to Co. Antrim. Patrick Adair of Antrim became famous as the author of a major Presbyterian tract. <ref>Plean, Squire, Encyclopedia, 348</ref> Adairs emigrated onwards to North America. James Adair (d.1783) was an American pioneer and wrote one of the earliest European studies of Native Americans. <ref>Plean, Squire, Encyclopedia, 348</ref>
Two families with the surname Adair are recorded in the register of the Lyon Court, those of Kinhilt and Genoch.<ref>Plean, Squire, Encyclopedia, 348</ref> The Adair Baronetcy, which became extinct in 1988, was created in 1838 for Robert Shafto Adair. <ref>http://en.wikipedia.org/wiki/Adair_baronets</ref>Robert Shafto was a landowner from Ballymena in Co. Antrim, whose origins in the area date to a grant of land by King Charles I in 1626. <ref>http://en.wikipedia.org/wiki/Robert_Adair,_1st_Baron_Waveney</ref>His son, Robert Shafto Adair, 1st Baron Waveny, was a British politician. <ref>http://en.wikipedia.org/wiki/Robert_Adair,_1st_Baron_Waveney</ref>