1) Having a valency of eight 
• (a.) Having a valence of eight; capable of being combined with, exchanged for, or compared with, eight atoms of hydrogen; -- said of certain atoms or radicals.
(ok″tә-va´lәnt) having a valency of eight.
Oc·tav'a·lent adjective [ Octa- + Latin valens , present participle See Valence .] (Chemistry) Having a valence of eight; capable of being combined with, exchanged for, or compared with, eight atoms of hydrogen; -- said of certain atoms or radicals. 
Type: Term Pronunciation: ok′tă-vā′lent, ok-tav′ă-lent Definitions: 1. Denoting a chemical element or radical having a combining power (valency) of eight. Synonyms: octad1