Union suit

A union suit is a type of one-piece long underwear. Created in Utica, New York, United States, it originated as women's wear during the 19th-century United States clothing reform efforts, as an alternative to constricting garments, and soon gained popularity among men as well. The first union suit was patented in 1868 as "emancipation union under flannel". Traditionally made of red flannel with long arms and long legs, it buttoned up the front and had a button-up flap in the rear covering the buttocks (colloquially known as the "access hatch", "drop seat", "fireman's flap", and other names). Depending on the size, some union suits can have a dozen buttons on the front to be fastened through buttonholes from the neck down to the groin area.

The garment remained in common use in North America into the 20th century. As its popularity waned, it became chiefly working men's wear, increasingly replaced by two-piece long underwear, also known as "long johns". It was not uncommon until the mid-20th century for rural men to wear the same union suit continuously all week, or even all winter. Normally, no other type of underwear was worn with it. In the 21st century, the garment has become popular among Millennials as loungewear or pajamas.

Union suits are still commercially available, but because of their long association with "old fashioned" usage, and presumed "unsophisticated" rural wearers, they are considered comical. The rear flap is also associated with humor, and in film and television the appearance of a union suit, viewed from behind, is a form of mild toilet humor. The 1999 movie adaptation of The Wild Wild West, Back to the Future Part III, the TV series Rugrats, and the Family Guy episode "No Meals on Wheels" are among those that used the rear flap on union suits for comical effects.

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