Word ladder or "Doublets", a word game invented by Lewis Carroll

In textual criticism, two different narrative accounts of the same actual event

A derivative of the Dirac delta function

Doublet (linguistics), one of two or more words of the same language that come from the same root

Doublet (clothing), a man's snug-fitting buttoned jacket that was worn from the late 14th century to the mid 17th century

Doublet (physics), a quantum state of a system with a spin of 1/2

Doublet (lens), a type of lens, made up of two stacked layers with different refractive indices

Dimeresia howellii, a tiny flowering plant.

Doublet (lapidary), an assembled gem composed in two sections, such as a garnet overlaying green glass