n. [ In sense 3, OF. doublet; in sense 4, F. doublet, dim. of double double. See Double, a. ] 1. Two of the same kind; a pair; a couple. [ 1913 Webster ]

2. (Print.) A word or words unintentionally doubled or set up a second time. [ 1913 Webster ]

3. A close-fitting garment for men, covering the body from the neck to the waist or a little below. It was worn in Western Europe from the 15th to the 17th century. [ 1913 Webster ]

4. (Lapidary Work) A counterfeit gem, composed of two pieces of crystal, with a layer of color between them, and thus giving the appearance of a naturally colored gem. Also, a piece of paste or glass covered by a veneer of real stone. [ 1913 Webster ]

5. (Opt.) An arrangement of two lenses for a microscope, designed to correct spherical aberration and chromatic dispersion, thus rendering the image of an object more clear and distinct. W. H. Wollaston. [ 1913 Webster ]

6. pl. (See No. 1.) Two dice, each of which, when thrown, has the same number of spots on the face lying uppermost; as, to throw doublets. [ 1913 Webster ]

7. pl. [ Cf. Pr. doblier, dobler draughtboard. ] A game somewhat like backgammon. Halliwell. [ 1913 Webster ]

8. One of two or more words in the same language derived by different courses from the same original from; as, crypt and grot are doublets; also, guard and ward; yard and garden; abridge and abbreviate, etc. [ 1913 Webster ]

n. The bar, or crosspiece, of a carriage, to which the singletrees are attached. [ 1913 Webster ]

n. pl. See Doublet, 6 and 7. [ 1913 Webster ]