Peer review
Also called: refereeing
The process by which independent researchers in a field evaluate a manuscript before a journal agrees to publish it.
An editor sends a submission to two or more reviewers who assess method, evidence, and originality, and recommend acceptance, revision, or rejection. Most work is revised at least once. The reviewers are usually unpaid and anonymous.
Blinding varies. Single-blind hides the reviewers from the author; double-blind hides both; open review publishes the reports and sometimes the names. Post-publication review inverts the order entirely.
Peer review is a filter, not a guarantee. It catches method errors and overclaiming reasonably well and fraud poorly, and reviewers disagree with each other more than outsiders expect. “Peer-reviewed” is a meaningful signal about a source, not a verdict on whether it is right.