Semi-formal

In Western clothing semi-formal is a grouping of dress codes indicating the sort of clothes worn to events with a level of protocol between informal (e.g., lounge suit) and formal. Both morning and evening semi-formal attire share design features in common with the informal lounge suit. In the modern era, semi-formal attire for men includes wearing a dark business suit, a cocktail dress is customary for women.

Whether one would choose to wear morning or evening semi-formal has traditionally been defined by whether the event will commence before or after 6:00 p.m.

In the daytime (before six o'clock), the semi-formal code requires for men a black tail-less coat with formal (vertical black & grey stripes, or checked) trousers, with a black waiscoat. This combination is a less formal version of morning dress, which features a longer, cutaway morning coat. This semi-formal ensemble is sometimes referred to as a "stroller" in North America, or a Marlborough suit in the UK. Because black was then reserved for formalwear, it was unknown as a color for lounge suits, so the term was unambiguous. In the UK this mode of dress is now extremely unusual, though some Masonic Lodges which meet during the day rather than (as is more common) in the evening do continue to specify it as their dress code. It also still is worn within the legal profession, especially by barristers. Indeed, the striped trousers are in some circles referred to as "barrister trousers". In German, a stroller is called a Stresemann, after the German foreign secretary Gustav Stresemann. Stresemann, like other German politicians of his age, wore morning dress or a frock coat in the Reichstag or when making public appearances. However, Stresemann found the long coat impractical for daily work in the Chancellery. To avoid having to change completely, he began to wear the prototype of this jacket at his office, while switching to a morning coat when engaged on more formal business. The style quickly caught on as a more practical variation on morning dress. In Japan, it is known as a "director's suit", from the term inside director.

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