Definition of: doublet

(dub′lit) noun
1. One of a pair of like things; a pair or couple.
2. A short, close-fitting, outer garment, with or without sleeves, worn by men from the 15th to 17th centuries.
3. An imitation gem consisting of a real stone cemented to a piece of glass colored to simulate the imitated gem; also, a paste jewel mounted with a thin face of a genuine jewel.
4. Ling. One of a pair of words derived from the same original but entering a language through different routes, as regal and royal.
5. Usually plural A pair of dice that, when thrown, show on the upper surface the same number of spots: He threw doublets.
6. Optics A pair of lenses joined so as to eliminate the distortion caused by either lens used alone. [<OF, something folded, orig. dim. of DOUBLE]
DOUBLET
(def. 2)