资料来源 : pyDict

七价的

资料来源 : Webster's Revised Unabridged Dictionary (1913)

Heptavalent \Hep*tav"a*lent\, a. [Hepta- + L. valens, p. pr. See
   {Valence}.] (Chem.)
   Having seven units of attractive force or affinity; -- said
   of heptad elements or radicals.