In chemistry the term stannate refers to compounds of tin (Sn). Stannic acid (Sn(OH)4), the formal precursor to stannates does not exist and is actually a hydrate of SnO2. The term is also used in naming conventions as a suffix for example the hexachlorostannate ion is SnCl62−. In materials science, two kinds of tin oxyanions are distinguished: ...
• (n.) A salt of stannic acid.
Stan'nate noun [ Confer French stannate .] (Chemistry) A salt of stannic acid. 
a salt of a stannic acid.