Definition from Wiktionary, the free dictionary
gunman (plural gunmen)
- A criminal armed with a gun, especially a professional killer.
1921, Zane Grey, chapter 5, in To The Last Man:
- "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."
criminal armed with a gun