Elenchus is a word, borrowed into English from Latin, which typically means some kind of refutation or cross-examination. It may refer to:
- Elenchus (brachiopod) <small>Gray, 1843</small>, a genus of brachiopods that is a synonym of Weiningia
- Elenchus (insect) <small>Curtis, 1831</small>, a parasitic insect genus in the family Elenchidae
- Elenchus (book), a third-century book also known as Refutation of All Heresies
- Method of elenchus, a form of cooperative argumentative dialogue, that is the central technique of the Socratic method