A tuxedo (US, colloquially "tux"), dinner jacket (UK, colloquially "DJ"), or dinner suit is a semi-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 dinner jacket along with suit evolved out of the smoking jacket - essentially a less formal evening wear without tail - following the example of the then Prince, later King Edward VII.
The suit is typically black or midnight blue and commonly worn with a formal shirt, shoes and other accessories, most traditionally in the form prescribed by the black tie dress code.
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