A garment worn beneath a shirt, an under-shirt is an essential clothing piece in a man's wardrobe. However, under-shirt can also be referred to by different names, including undershirt, singlet, vest, tank top, and wife-beater, among others. Undershirt is the most common among the synonyms as it is often used interchangeably with under-shirt. Singlet, on the other hand, is a term used mainly in the UK and Australia to describe an under-shirt with slim shoulder straps. Vest is another term that is often used to describe an under-shirt that covers the torso. Wife-beater is also another name used to describe a certain type of under-shirt that is sleeveless with a tight fit and made of ribbed cotton.