1) Salt 
In chemistry, a vanadate is a compound containing an oxoanion of vanadium generally in its highest oxidation state of +5. The simplest vanadate ion is the tetrahedral, orthovanadate, VO43− anion, which is present in e.g. sodium orthovanadate and in solutions of V2O5 in strong base (pH > 13 ). Conventionally this ion is represented with a single ...
• (n.) A salt of vanadic acid.
VO4(3) Powerful inhibitor of many, but not all enzymes that cleave the terminal phosphate bond of ATP. The vanadate ion is believed to act as an analogue of the transition state of the cleavage reaction. Dynein is very sensitive to inhibition by vanadate, whereas kinesin is relatively insensitive. Similarly tyrosine kinases are sensitive to vanadat...
(= VO43-) Powerful inhibitor of many, but not all enzymes that cleave the terminal phosphate bond of ATP. The vanadate ion is believed to act as an analogue of the transition state of the cleavage reaction. Dynein is very sensitive to inhibition by vanadate, whereas kinesin is relatively insensitive. Similarly tyrosine kinases are sensitive to vanadate, but threonine/serine protein kinases are insensitive.
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Van'a·date noun [ Confer French vanadate .] (Chemistry) A salt of vanadic acid. [ Formerly also vanadiate .] 
Type: Term Pronunciation: van′ă-dāt Definitions: 1. A salt of vanadic acid.
[n] - a salt or ester of vanadic acid
noun a salt or ester of vanadic acid; an anion containing pentavalent vanadium