What is Infant bodysuit?

An infant bodysuit or onesie is a garment designed to be worn by babies much like a T-shirt; they are distinguished from T-shirts by an extension below the waist, with snaps that allow it to be closed over the crotch. The purpose of the opening at the crotch is to facilitate access to the infant's diaper as well as preventing the garment from riding up the infant's body and exposing skin. Like T-shirts, infant bodysuits come in a wide variety of designs and may be worn as undergarments or as outer shirts.