gunman /ˈɡʌnmən/noun 2forms 1phrases 1 noun2 •A person armed with a gun, especially a gunned evildoer."I've known a heap of gun fighters in my day. An' Jean Isbel don't ran true to class. Shore there never was a gunman who'd risk cripplin' his right hand by sluggin' anybody." — 1921 •(offensive) An American. formsgunmen Phrases with gunman lone gunmanAn individual person who acts on his or her own initiative, without partners, especially one who has sole responsibility for doing something questionable, confidential, or iniquitous.