A tuxedo (American English, also colloquially known as “tux”) or dinner suit, dinner jacket or DJ (British English - "dinner jacket" - describing both jacket and trousers is held to be more "correct" - "dinner suit" is regarded as a solecism[citation needed]) is a formal evening suit distinguished primarily by satin or grosgrain facings on the jacket's lapels and buttons and a similar stripe along the outseam of the trousers. The suit is typically black or midnight blue depending on choice of wear and commonly worn with a formal shirt, shoes and other accessories, most traditionally in the form prescribed by the black tie dress code.