Anovervote occurs when one votes for more than the maximum number of selections allowed in a contest.[1] The result is a spoilt vote which is not included in the final tally.
One example of an overvote would be voting for two candidates in a single race with the instruction "Vote for not more than one." Robert's Rules of Order notes that such votes are illegal: "If he votes for too many candidates for a given office, however, that particular section of the ballot is illegal, because it is not possible for the tellers to determine for whom the member desired to vote."[2]
Undervotes combined with overvotes (known as residual votes) can be an academic indicator in evaluating the accuracy of a voting system when recording voter intent.Cite error: A <ref> tag is missing the closing </ref> (see the help page).
In the corporate world, the term "overvote" describes a situation in which someone votes more proxies than they are authorized to, or for more shares than they hold of record.[3]