(1):

(n.) In the old German empire, one of the princes entitled to choose the emperor.

(2):

(a.) Pertaining to an election or to electors.

(3):

(n.) One of the persons chosen, by vote of the people in the United States, to elect the President and Vice President.

(4):

(n.) Hence, specifically, in any country, a person legally qualified to vote.

(5):

(n.) One who elects, or has the right of choice; a person who is entitled to take part in an election, or to give his vote in favor of a candidate for office.