noun which may take the genitive case particle 'no'
gentlemanly; gentlemanlike
Describes a person, behavior, or appearance that is refined, courteous, and dignified, like a gentleman. Often used with な or の.
I was impressed by his gentlemanly manner.
He attended the party in gentlemanly attire.
Compound of 紳士 (gentleman) + 風 (style/manner).