Q. What are men's vests called?

Answer

Waistcoats also known as vests in the United States and Canada and as weskits in the United Kingdom and Commonwealth are sleeveless tops that cover the torso but leave the arms bare. Nowadays when people talk about a gilet they usually mean a simple structured straight-sided sleeveless jacket used for supplementary warmth on chilly days (also called a bodywarmer waistcoat or vest in the US). Waistcoats are a common component of men's suits; they are the sleeveless top worn over a collared shirt and preceding the jacket. In all practical purposes a waistcoat can be thought of as an elaborate vest.