The bow tie /boʊ/ is a type of necktie. A modern bow tie is tied using a common shoelace knot, which is also called the bow knot for that reason. It consists of a ribbon of fabric tied around the collar of a shirt in a symmetrical manner, so that the two opposite ends form loops.

There are generally three types of bow ties: the pre-tied, the clip on, and the self tie. Pre-tied bow ties are ties in which the distinctive bow is sewn onto a band that goes around the neck and clips to secure. Some "clip-ons" dispense with the band altogether, instead clipping straight to the collar. The traditional bow tie, consisting of a strip of cloth which the wearer has to tie by hand, is also known as a "self-tie", "tie-it-yourself", or "freestyle" bow tie.

Bow ties may be made of any fabric material, but most are made from silk, polyester, cotton, or a mixture of fabrics. Some fabrics (e.g., wool or velvet) are much less common for bow ties than for ordinary four-in-hand neckties.

A tailcoat is a knee-length coat characterised by a rear section of the skirt, known as the tails, with the front of the skirt cut away.

The tailcoat shares its historical origins in clothes cut for convenient horse riding in the Early Modern era. Ever since the 18th century, however, tailcoats evolved into general forms of day and evening formal wear, in parallel to how the lounge suit succeeded the frock coat (19th century) and the justacorps (18th century).

Thus, in 21st-century Western dress codes for men, mainly two types of tailcoats have survived:

Dress coat, an evening wear with a squarely cut away front, worn for formal white tie
Morning coat (or cutaway in American English), a day wear with a gradually tapered front cut away, worn for formal morning dress
In colloquial language without further specification, "tailcoat" typically designates the former, that is the evening dress coat for white tie.