Does any political system in the world have electoral vote weighting based on the voter's fiscal contribution? The premise being that the taxes paid are a reasonable approximation of merit and value to society that should determine how much the vote counts. What would be a name for such a policy doctrine?
This sounds like weighted voting.
I do not believe that there is a specific name for weighting the vote based on taxes, but a description for the system as a whole would be plutocracy.
I do not believe that there are any countries that actually practice this form of voting - it would be in conflict with the principles of democracy - universal suffrage, one man one vote, etc - , and undemocratic countries generally do not require a voting system in the first place. Note also that it would not work well with the secrecy of the ballot, which is another important principle for most democracies.