Young Brunette Girl With Pigtails Undresses Her Blue Chemise On The Bank Of The River

The term pigtail appears in English in the American colonies in the 17th century to describe a twist of chewing tobacco. One of the steps in processing the tobacco was to twist a handful of leaves together to form a compact bunch that would then be cured (dried, either with or without smoking). The term "pigtail" was applied to the bunch based on its resemblance to a twisted pig's tail.
From the later 17th century through the 19th century, the term came to be applied to any braided (plaited, in British parlance) hairstyle. The British army also adopted a single pigtail or "queue" as its standard dress for long hair.
Robert Louis Stevenson mentions "pigtail" referring to hair and then to "pigtail tobacco" in the first and fourth chapters of Treasure Island, respectively.
Most dictionaries still define "pigtail" as a single tight braid. However, many American English speakers use the term to describe two symmetrical bunches of hair on either side of the head, braided or not. In some cases, the term only applies to unbraided hair. This usage of the term can be seen on personal and professional websites devoted to hairstyles or even by typing "pigtails" into a search engine.