Dinner jacket

A dinner jacket (British English) or tuxedo (American English, also colloquially known as "tux"), dinner suit, or DJ 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 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.

Dinner jacket in the context of menswear first appeared in England around 1887 and in the US around 1889. In the 1960s it became associated in the United States with white or colored jackets specifically.

Tuxedo in the context of menswear originated in the US around 1888. It was named after Tuxedo Park, a Hudson Valley enclave for New York’s social elite where it was often seen in its early years. The term was capitalized until the 1930s and at first referred only to the jacket. When the jacket was later paired with its own unique trousers and accessories in the 1900s the term began to be associated with the entire suit.

In French, Italian, Portuguese, German, Polish, Russian, Turkish, and other European languages the jacket is called a smoking and in Spanish it is an esmoquin. This name is in reference to the jacket’s early similarity to Victorian smoking jackets.

The suit with accompanying accessories is sometimes nicknamed a penguin suit given its resemblance to the bird's black body and white chest. Other slang terms include monkey suit and, since 1918, soup and fish.

In the 1860s, the increasing popularity of outdoor activities among the British middle and upper classes led to a corresponding increase in the popularity of the casual lounge suit (standard suit in American English) as a country alternative to the more formal day wear that was traditionally worn in town. Men also sought a similar alternative to the formal evening tailcoat (then known as a "dress coat") worn every evening.

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