The Collaborative International Dictionary of English v.0.48:

Zincous \Zinc"ous\, a.
   1. (Chem.)
      (a) Of, pertaining to, or containing, zinc; zincic; as,
          zincous salts.
      (b) Hence, formerly, basic, basylous, as opposed to
          chlorous.
          [1913 Webster]

   2. (Physics) Of or pertaining to the positive pole of a
      galvanic battery; electro-positive.
      [1913 Webster] zine