n. The English form of the Latin word porphyrites, used by the Romans to designate a certain rock having a dark-crimson ground through which are scattered small crystals of feldspar.n. A slab of porphyry, used in alchemy.n. In zoology, a porphyry-moth.n. In ceramics, a hard colored body made by Josiah Wedgwood, in imitation of porphyry.