Emily Dickinson Lexicon

DOUB'LET, n. [Ir. duiblead; Fr. doublet.]

1. The inner garment of a man; a waistcoat or vest.
2. Two; a pair. – Grew.
3. Among lapidaries, a counterfeit stone composed of two pieces of crystal, with a color between them, so that they have the same appearance as if the whole substance of the crystal were colored. – Encyc.