Doublet is a word derived from the Latin duplus, "twofold, twice as much", and is used to indicate a pair of identical, similar, or related things.

Doublet may refer to:

Apparel Doublet (clothing), a man's snug-fitting buttoned jacket that was worn from the late 14th century to the mid 17th century Doublet (Highland dress), a formal jacket worn with Scottish highland dress

Games Doublet (dominoes), a domino tile in which both ends have the same value Doublets (game), old English tables game in the same family as Backgammon Word ladder or "doublets", a word game invented by Lewis Carroll

Language Doublet (linguistics), two or more words of the same language that come from the same etymon Doublet, in textual criticism, two different narrative accounts of the same actual event Legal doublet, a standardized phrase in English legal language consisting of two (or more) words

Science and technology Doublet (computing), a group of 16 bits in computing Doublet (lens), a type of lens, made up of two stacked layers with different refractive indices Doublet (potential flow), fluid flow due to a source–sink combination Doublet, or dimeresia howellii, a tiny flowering plant Doublet earthquake, two earthquakes associated by space and time Doublet state, a state in quantum physics of a system with a spin of Unit doublet, in mathematics, the derivative of the Dirac delta function

Other uses Doublet (horse), (b. 1963 - †.1974), a thoroughbred gelding Doublet (lapidary), an assembled gem composed in two sections, such as a garnet overlaying green glass Doublet (hunt), two shots from a double barrel, coming one after another Pierre Jean Louis Ovide Doublet (1749–1824), French politician and writer affiliated with the Order of Malta Michel Doublet (1939–2022), French politician.