doublet

A doublet is usually a special kind of pair rather than just anything that comes in twos. In history, it is best known as a close-fitting jacket worn by men in Europe from about the 14th to the 17th centuries. In language, it can mean a pair of words that came from the same source but entered English in different ways, such as frail and fragile. The word can also be used for something made of two joined parts, such as a gem made from two layers, or for a repeated word or line in old printing.

The history of the word "doublet" is tied to the idea of something doubled. In its oldest common sense, it meant a garment made from doubled cloth. Over time, that became the well-known close-fitting jacket worn by men in Europe from the late Middle Ages into the Renaissance. A doublet could be padded, decorated, and worn with hose, and it was a central part of men's dress before later coats replaced it.

Beyond clothing, "doublet" has several other meanings built around the idea of two linked parts. In linguistics, doublets are pairs of words that come from the same origin but entered English by different paths, such as hostel and hotel or warranty and guarantee. In jewelry, a doublet is a stone made by joining two layers so that it looks like a single gem. In printing, a doublet is an error in which a letter, word, line, or passage is accidentally repeated.

Whether you meet the word in a history book, a language lesson, a jewelry description, or an old printing manual, "doublet" keeps the same basic idea: two connected parts showing up as one item, one pair, or one repeated form.