Onesies

Since the 2000s, onesie has become a commonly used word for a particular style of loose-fitting casual jumpsuits for adults made of knit cotton as used in sweatshirts, fleece, or chenille. They are mostly intended as loungewear or sleepwear, but have gained significant popularity as stylish streetwear, especially in the UK and Australia, the onesie became very popular during the late 2000s and early 2010s as a street fashion. Onesie was originally a term for an infant bodysuit, probably derived from Onesies, which is a registered trademark for a certain range of infants' clothes.