tetravalent

from WordNet (r) 3.0 (2006)

tetravalent
    adj 1: haveing a valence of four

from The Collaborative International Dictionary of English v.0.48

Tetravalent \Te*trav"a*lent\, a. [Tetra- + L. valens, -entis, p.
   pr.] (Chem.)
   Having a valence of four; tetratomic; quadrivalent.
   [1913 Webster]