Of a man : dressing and acting in an appealing and sophisticated way : fashionable, attractive and confident
1) I saw a debonair man in a suit and top hat.
2) His debonair dismissal of my inquiry concerning his financial situation led me to believe that nothing was wrong.
From Anglo-French deboneire, from de bon aire of good family or nature.
blithe, carefree, devil-may-care, charming, gracious
unsophisticated, inelegant, uncharming