Doublet may refer to: Doublet (clothing), a man's snug-fitting buttoned jacket that was worn from the late 14th century to the mid 17th century Doublet (lapidary), an assembled gem composed in two sections, such as a garnet overlaying green glass Doublet (lens), a type of lens, made up of two stacked layers with different refractive indices Doublet (linguistics), one of two or more words of the same language that come from the same root Doublet (physics), a quantum state of a system with a s… (More on Doublet)