adult baby syndrome

Meanings

1. A condition or desire in which one takes on the role of an infant or toddler, usually by wearing diapers, engaging in child-like activities and engaging with childish paraphernalia, whether sexual (autonepiophilia) or non-sexual; infantilism, often believed to be the result of childhood trauma, neglect or abuse.

Etymology

From adult baby + syndrome. First attested as early as 21 March 1994, but popularised in academia by a 2003 research paper (see quotations).