1. A man who is the lover of a man or woman
   "if I'd known he was her swain I wouldn't have asked";
   - boyfriend, fellow, beau [archaic], boyf [Brit, informal]

Derived forms: swains

Type of: adult male, bozo [N. Amer, informal], cat [N. Amer, informal], chappie [Brit, informal], geezer [Brit, informal], guy [informal], hombre [N. Amer, informal], lover, man, sod [informal]

Encyclopedia: Swain, Norwegian ruler for Canute the Great