AIRE, a city of France, head of a canton of the same name, in the circle of St Omer, and department of Pas de Calais. It is situated on the river Lys. The population amounts to 5088 persons, who are chiefly employed in making cotton and woollen goods, hardware, and large quantities of oil from seeds. Long. 2. 24. E. Lat. 50. 38. N.