Mother's boy, also called mama's boy, is a term for a man who is excessively attached to his mother at an age when men are expected to be independent (e.g. live on their own, be economically independent). A mother's boy may be effete or effeminate, or might be perceived as being macho, or might have a personality disorder, such as avoidant personality disorder, or might be schizophrenic, so that the mother acts as a caretaker. In any case, a mother's boy cannot maintain a healthy partnership with a woman (Carruthers, 1998).
Being mother-bonded is sometimes seen as a sign of weakness, and has a social stigma attached to it in many places, although in other places it may be more acceptable or perceived as normal. A mother-bonded man is seen to give control of his own life to his mother, in exchange for a sense of security. If the mother has more than one son, then she will have, at the most, one mother's boy, usually the eldest son. The relationship between mother and mother's boy is thought to be "symbiotic": the mother enjoys controlling her mother's boy.
Alternatively, in recent years, some have begun using the term in a milder sense, merely meaning a man who is emotionally attached to his mother. Though this sense of the phrase is still uncommon compared to the original pejorative intent, mothers in particular may state their pride in their "mama's boy" sons. It is also occasionally used to describe an infant or toddler son who is unusually attached to his mother, even crying or resisting when the father attempts to care for him. In this sense, the 'mama's boy' designation carries little stigma, but is simply an observation of the young child's primary attachment.