Paraphilic infantilism
Paraphilic infantilism, also known as adult baby (or "AB", for short), is a form of ageplay that involves role-playing a regression to an infant-like state. Like other forms of adult play, depending on the context and desires of the people involved, paraphilic infantilism may be expressed as a non-sexual fetish, kink, or simply as a comforting platonic activity.