Quadrivalent \Quad*riv"a*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.
[1913 Webster]