Source : Webster's Revised Unabridged Dictionary (1913)

Gentlemanlike \Gen"tle*man*like`\, Gentlemanly \Gen"tle*man*ly\,
   a.
   Of, pertaining to, resembling, or becoming, a gentleman;
   well-behaved; courteous; polite.

Source : WordNet®

gentlemanly
     adj : befitting a man of good breeding; "gentlemanly behavior"
           [syn: {gentlemanlike}]