Of, being, pertaining to, or resembling a gentleman or gentlemen.
2010, Catherine Rampell, “In Law Schools, Grades Go Up, Just Like Thatâ€, in The New York Times, 2010 June 22, page A1:Some schools bump up everyone’s grades, some just allow for more As and others all but eliminate the once-gentlemanly C.
1938, Charles A. Johnson, A Narrative History of Wise County, Virginia (page 165)He went gentlemanly dressed in East Virginia style, wore a high-top silk hat, as had lawyer Park, and sported a gold headed walking cane.