A soft or effeminate boy or man; a male overly attached to his mother: the stale old mama's-boy-liberated-by-looneylovely(1896+)
Idioms and Phrases with mama's boy
mama's boy
A sissy, especially a boy or man excessively attached to his mother. For example, The children called Tom a mama's boy because he ran home with every little problem. This sexist expression has survived despite its pejorative tone. [ ; mid-1800s ]