1540s, "small ball used in voting," also "secret vote taken by ballots," from Italian pallotte, diminutive of palla "ball," for small balls used as counters in secret voting (see balloon). Earliest references are to Venice. By 1776 extended to tickets or sheets of paper used in secret voting. Ballot box attested from 1670s; metonymically from 1834 as "system or practice of voting by ballot."
ballot (v.)
1540s, from ballot (n.). Related: Balloted; balloting.