Word Study
stannic
CIDE DICTIONARY
stannic, a. [L. stannum tin: cf. F. stannique.].
Of or pertaining to tin; derived from or containing tin; specifically, designating those compounds in which the element has a higher valence as contrasted with stannous compounds. [1913 Webster]
OXFORD DICTIONARY
stannic, adj. Chem. of or relating to tetravalent tin (stannic acid; stannic chloride).
Etymology
LL stannum tin
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