1. Election held to determine which candidates qualify to appear as contest options in subsequent elections.
Source: Election Terminology Glossary - Draft, National Institute of Standards and Technology (NIST), https://pages.nist.gov/ElectionGlossary/
2. Election held to determine which candidate will represent a political party for a given office in the general election. Some states have an open primary, while others have a closed primary. Sometimes elections for nonpartisan offices and ballot issues are held during primary elections. Version 1.0 Volume I: Voting System Performance Guidelines Appendix A: Glossary A-15.
Source: Glossary of terms database, U.S. Election Assistance Commission, https://www.eac.gov/glossary/