alas I. \əˈlas, -aa(ə)s, -ais, -ȧs\interjection Etymology: Middle English, from Old French, from a ah + las weary, wretched, from Latin lassus weary — more at let — used to express unhappiness, sorrow, pity, or concern < alas for their sad fate > < alas the heavy day > II. \ˈäˌläs\noun (pluralalas) Usage: usually capitalized 1.: an Indonesian people of northern Sumatra 2.: a member of the Alas people