Of, being, pertaining to, or resembling a gentleman or gentlemen.(adjective)
In the manner or with the behavior of a gentleman; with social grace, politely.(adverb)
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Use "gentlemanly" in a sentence
"He did not mind their sowing of wild oats if they were what he called gentlemanly wild oats, and merely got them talked about as gay young dogs, and he was always generous with an extra cheque if they got into difficulties; but he would not have foolhardy, quixotic affairs at all."
"It may be repugnant to one to have people you know and trust be accused of committing a crime — that may not be done in gentlemanly society — but counting on gentlemanly diffidence among members of the elite assures, at least to me, that the hard questions do not getasked."
"So in gentlemanly fashion, we help the ladies up, and preferably, lots of ladies, and we call it what it is, a Party on the Roof."