blacktie
Black tie is a formal dress code used for evening social events, typically after 5 pm. The term stems from the traditional accessory most associated with the outfit: a black bow tie worn with a tuxedo or dinner jacket. In invitations, the phrase signals a high level of formality and a dress expectation beyond business or casual wear.
For men, the standard black-tie ensemble is a tuxedo or dinner jacket in black or midnight blue,
For women, attire generally centers on a floor-length evening gown, though in some contexts a very dressy
Variants of the dress code include black tie optional (allowing a dark suit or a tuxedo), and