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Aird
Scottish: habitational name from a place named with Gaelic àird(e) ‘height’, ‘promontory’, or ‘headland’, from the adjective àrd ‘high’, ‘lofty’, cognate with Latin arduus ‘steep’, ‘difficult’. There is one such place near Hurlford in Ayrshire, and another in Inch, Wigtownshire. See also Ard.
Ard
Scottish: habitational name from any of several places called Aird, including one near Hurlford in Ayrshire, another near Stranraer in Galloway, and the Aird, the higher part of the Vale of Beauly, near Inverness. These place names are derived from Gaelic àird(e) ‘height’, ‘promontory’, from àrd ‘high’.