|1.||(formerly) a man's close-fitting jacket, with or without sleeves (esp in the phrase doublet and hose.)|
|2.||a. a pair of similar things, esp two words deriving ultimately from the same source, for example reason and ratio or fragile and frail|
|b. one of such a pair|
|3.||jewellery a false gem made by welding a thin layer of a gemstone onto a coloured glass base or by fusing two small stones together to make a larger one|
|a. a multiplet that has two members|
|b. a closely spaced pair of related spectral lines|
|5.||(plural) two dice each showing the same number of spots on one throw|
|6.||physics two simple lenses designed to be used together, the optical distortion in one being balanced by that in the other|
|[C14: from Old French, from |
doublet dou·blet (dŭb'lĭt)
A pairing of two lenses to optically correct a chromatic and spherical aberration.
chief upper garment worn by men from the 15th to the 17th century. It was a close-fitting, waisted, padded jacket worn over a shirt. Its ancestor, the gipon, was a tunic worn under armour, and at first it came down almost to the knees. The civilian doublet at first had skirts but gradually lost them. It had no collar until 1540, allowing the shirt to be seen at the neck; the shirt was also visible through slashes or pinking in the material.
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