Not gentlemanly; not adhering to the high moral standards expected of a gentleman; impolite, unchivalrous, or indecent.(adjective)
Wiktionary.org : Text is available under the Creative Commons Attribution-ShareAlike License
Use "ungentlemanly" in a sentence
"He was further described as ungentlemanly by a brace of spinsters who had been within earshot on the veranda the morning he had abused the Asquith roads, but their evidence was not looked upon as damning."
"While his later behavior could conservatively be called ungentlemanly, I have no doubt Hilton wanted Carrie Prejean to give a different answer than she did, not because he had an "agenda," but because he wanted her to be kind as well as beautiful."
"He pushed caution to such extremes that you can only call ungentlemanly where"