Pro`to*met"als (?), n. pl.
A finer form of metals, indicated by enhanced lines in their spark spectra (which are also observed in the spectra of some stars), obtained at the highest available laboratory temperatures (Lockyer); as protocalcium, protochromium, protocopper, protonickel, protosilicon, protostrontium, prototitanium, protovanadium. -- Pro`to*me*tal"ic (#), a.
© Webster 1913