A vest is a type of collarless sleeveless upper-body garment. There are a variety of similar garments that can be referred to as vests, but may go by other names in different regions. Vests typically fall into two broad categories:Sleeveless upper-body garments, usually worn as undergarments, known as vests, undershirts or singlets;Sleeveless jackets or coats, known as vests in the US and as waistcoats in the UK and Ireland.

embroidered tunicThe garment known as a waistcoat in the UK and many commonwealth countries and as vest in North America, is a sleeveless jacket or coat. It is often worn as part of formal attire, as the third piece of the three-piece suit.

Inflatable SliderA form of this garment, sometimes known as a sports vest, is worn as an outer garment, usually in association with outdoor activities. The padded vest is popular apparel for hunting, commonly known as a hunting vest. Another common variant is the fishing vest which carries a profusion of external pockets for carrying fishing tackle.

The term vest derives from French veste, Italian vesta, veste "robe, gown," and Latin vestis, from vestire "to clothe". The sleeveless garment worn by men beneath the coat may have been introduced by King Charles II of England; a diary entry from October 8, 1666, written by Samuel Pepys states, "The King hath yesterday, in Council, declared his resolution of setting a fashion for clothes .... It will be a vest, I know not well how; but it is to teach the nobility thrift."