divalent

from WordNet (r) 3.0 (2006)

divalent
    adj 1: having a valence of two or having two valences [syn:
           {bivalent}, {divalent}]

from The Collaborative International Dictionary of English v.0.48

Divalent \Div"a*lent\, a. [Pref. di- + L. valens, valentis, p.
   pr. See {Valence}.] (Chem.)
   Having two units of combining power; bivalent. Cf. {Valence}.
   [1913 Webster]