elector (n.)

c. 1300, eleccioun, "act of choosing" someone to occupy a position, elevation to office" (whether by one person or a body of electors); also "the holding of a vote by a body of electors by established procedure; the time and place of such a vote," from Anglo-French eleccioun, Old French elecion "choice, election, selection" (12c.), from Latin electionem (nominative electio) "a choice, selection," noun of action from past-participle stem of eligere "pick out, select," from ex "out" (see ex-) + -ligere, combining form of legere "to choose," from PIE root *leg- (1) "to collect, gather."

In Middle English also "act of choosing" generally, "choice, free choice" (c. 1400). The theological sense of "God's choice of someone" for eternal life is from late 14c. Meaning "act of choosing, choice" is from c. 1400.

1670s, "pertaining to electors," in reference to Germany, from elector + -al (1). In general sense from 1790. Related: Electorally. The U.S. electoral college so called from 1808 (the term was used earlier in reference to Germany).

1670s, "condition of being an elector," in reference to Germany, from elector + -ate (1). Meaning "whole body of voters" is from 1879.