According to Voltaire the wife makes the rules (3)
I believe the answer is:
law
'the rules' is the definition.
(I've seen this before)
'according to voltaire the wife' is the wordplay.
'according to voltaire the' becomes 'la' ('the' in French - Voltaire was French).
'wife' becomes 'w' (abbreviation).
'la'+'w'='LAW'
'makes' acts as a link.
(Other definitions for law that I've seen before include "Rule of conduct" , "Collection of rules for a society" , "Act" , "Commandment" , "Legislation" .)