Ar-chē'us, n.

n. [L. Lat. archēus, Gr. ἀρχαῖον, ancient, primeval, from ἀρχή, beginning. See ARCH, a.] The internal efficient cause of all things; the anima mundi, or plastic power of the old philosophers; the active principle of the material world and the power that presides over the animal economy; the vis mediatrix. [Obs.] Johnson. Coxe.