noun
1.
a person who has the right to vote in an election, especially one for members of a national parliament.
"close to 60 per cent of the 60,000 registered electors voted"
synonyms: voter, member of the electorate, enfranchised person, constituent, member of a constituency, selector
"each elector has one vote"
2.
HISTORICAL
a German prince entitled to take part in the election of the Holy Roman Emperor.
"the Elector of Brandenburg"