noun A pair of two similar or equal things; couple.
noun One of two or more different words in a language derived from the same etymological root but having different phonological forms (e.g., toucher and toquer in French or shade and shadow in English). See also Appendix:Glossary#doublet.
noun In textual criticism, two different narrative accounts of the same actual event.
noun An imitation gem made of two pieces of glass or crystal with a layer of color between them.
noun A word or phrase set a second time by mistake.
noun A quantum state of a system with a spin of ½, such that there are two allowed values of the spin component, −½ and +½.
noun A word (or rather, a halfword) consisting of two bytes.
noun A very small flowering plant, Dimeresia howellii.