1. Repeat tabulation of votes cast in an election, whether manually or electronically, that is used to determine the accuracy of an initial count.
Source: Election Terminology Glossary - Draft, National Institute of Standards and Technology (NIST), https://pages.nist.gov/ElectionGlossary/
2. Retabulation of the votes cast in an election.
Source: Glossary of terms database, U.S. Election Assistance Commission, https://www.eac.gov/glossary/
3. Some states authorize certain persons (e.g., defeated candidates and voters) to request an election recount under specified circumstances. These circumstances can include, for example, when there is a tie vote, when the margin of victory is within a specified percentage or number of votes, or when inaccuracies in the vote count are alleged. The scope and method of such recounts can vary to include, for example, partial recounts of certain precincts, complete recounts of all ballots, machine recounts, and hand recounts for the office or issue in question. Some states provide for mandatory (or automatic) recounts that are, for example, mandated in a specified percentage or number of precincts irrespective of victory margins, or triggered by a tie vote, or a margin of victory within a specified percentage or number of votes.
Source: ELECTIONS: The Nation’s Evolving Election System as Reflected in the November 2004 General Election, U.S. Government Accountability Office, https://www.gao.gov/assets/160/157713.pdf