Morning dress, also known as formal day dress, is the formal Western dress code for day attire, consisting chiefly of, for men, a morning coat, waistcoat, and formal trousers, and an appropriate gown for women. Men may also wear a popular variant where all parts are the same colour and material, often grey and usually called "morning suit" or "morning grey" to distinguish it; considered properly appropriate only to festive functions such as summer weddings and horse races, which consequently makes it slightly less formal. The correct hat would be a formal top hat, or if on less spacious audience settings optionally a collapsible equivalent opera hat.

Formal wear or full dress is the Western dress code category applicable for the most formal occasions, such as weddings, christenings, confirmations, funerals, Easter and Christmas traditions, in addition to certain state dinners, audiences, balls, and horse racing events. Generally permitted other alternatives, though, are the most formal versions of ceremonial dresses, full dress uniforms, religious clothing, national costumes, and most rarely frock coats. In addition, formal wear is often instructed to be worn with official full size orders and medals.