Black-tie dress code is
the tuxedo or dinner suit
Consisting of a single or double-breasted jacket with covered buttons and satin-covered lapels, trousers with a satin or grosgrain stripe down the sides and tabs or suspenders instead of belt loops. The most popular colors are black or midnight blue (both with black satin detailing).
Wear with a cuffed white dress shirt (with either a covered placket or evening studs and a turndown collar) and a bow tie. Footwear needs to be patent leather or shined lace-up shoes, opera pumps, or smoking slippers.