debonair (adj.) Look up debonair at
c. 1200, "mild, gentle, kind courteous," from Old French debonaire, from de bon' aire "of good race," originally used of hawks, hence, "thoroughbred" (opposite of French demalaire); aire here is perhaps from Latin ager "place, field" (from PIE root *agro- "field") on notion of "place of origin." Used in Middle English to mean "docile, courteous," it became obsolete and was revived with an altered sense of "pleasant, affable" (1680s).