• (p. pr.) Having a valence of six; -- said of hexads.
(hek″sә-va´lәnt) having a valence of six.
Hex·av'a·lent adjective [ Hexa- + Latin valens , -entis , present participle See Valence .] (Chemistry) Having a valence of six; -- said of hexads. 
hexavalent Combining with, or capable of, replacing six atoms of hydrogen or other univalent element or radical.