1. (Science: chemical) A mineral or rock consisting chiefly of the hydrous silicate of magnesia. It is usually of an obscure green colour, often with a spotted or mottled appearance resembling a serpent’s skin. Precious, or noble, serpentine is translucent and of a rich oil-green colour.
Serpentine has been largely produced by the alteration of other minerals, especially of chrysolite.
2. A kind of ancient cannon.
Origin: Cf. (for sense 1) F. Serpentine, (for sense 2) serpentin.