Webster’s Revised Unabridged Dictionary · 1913
Quadrivalent
Quad·riv′a·lent (·lent), a. [Quadri- + L. valens, -entis, p. pr. See Valence.] (Chem.) Having a valence of four; capable of combining with, being replaced by, or compared with, four monad atoms; tetravalent; — said of certain atoms and radicals; thus, carbon and silicon are quadrivalent elements.