For seven years now, Jon Hamm's debonair ad exec has been the existential question mark at the center of the series.
Matthew, like your co-star Hugh Grant in this movie, possesses a kind of debonair diffidence.
Cary Grant at home was more or less the same man the public saw in movies: debonair, decent, and funny.
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). Used in Middle English to mean "docile, courteous," it became obsolete and was revived with an altered sense of "pleasant, affable" (1680s).