Glossary
The specific movement design used in a watch, identified by a name or number that describes its construction and specifications.
A brand's catalog ties each reference to a specific caliber, so a movement that doesn't match the caliber a reference should carry is a clear inconsistency. Authenticators compare caliber markings, bridge shapes, and finishing against reference photography for that exact caliber, since a convincing case can still conceal the wrong movement inside.
Browse the full glossary, or look up a serial number in the registry.