1) Salt 
In inorganic nomenclature, a manganate is any negatively charged molecular entity with manganese as the central atom. However, the name is usually used to refer to the tetraoxidomanganate(2−) anion, MnO{su|b=4|p=2−}, also known as manganate(VI) because it contains manganese in the +6 oxidation state. Manganates are the only known manganese(VI)...
• (n.) A salt of manganic acid.
Man'ga·nate noun [ Confer French manganate .] (Chemistry) A salt of manganic acid. » The manganates are usually green, and are well-known compounds, though derived from a hypothetical acid.
[n] - a salt of manganic acid containing manganese as its anion
noun a salt of manganic acid containing manganese as its anion