Watch Glossary
1676 horological terms explained
All categoriesAccessoryAdjustmentAdministrationAestheticsAuction House TermsAuthenticationBezelBraceletBrandingBusinessCaseCase DesignCase FeatureCertificationClaspCleaningCollectingCollecting and MarketComplicationComplicationsConditionCondition GradingCrownCrystalDecorationDesignDetailDialDisplayDivingEnvironmentalEventsExtensionFeaturesFinishingHandsHeat TreatmentHistoryIconsIndustryInspectionLifestyleLink TypeMaintenanceManufactureMaterialsModelModernMovementOrganizationsPartsPlatingPrecisionRefinishingServiceStandardsStrapSurface CoatingSurface FinishingSurface TreatmentTechnicalTestingTimekeepingToolsTreatmentsVariantWatch JournalismWatch TypesWater Sports
C.O.S.C. CertificateCertification
Official document proving watch movement meets chronometer precision standards
Caseback Engraving Depth AnalysisCertification
Forensic evaluation of inscription cut-depth, tool marks, and letter spacing for period authenticity verification.
Chronometer RatingCertification
Official COSC certification grade indicating movement precision within specific tolerances
Chronometer StandardCertification
Set of rigorous testing criteria ensuring exceptional timekeeping precision.
Chronometric AccuracyCertification
Degree to which watch maintains precise and consistent timekeeping.
COSCCertification
Contrôle Officiel Suisse des Chronomètres - Swiss official chronometer testing institute
COSC ToleranceCertification
Chronometer standard: -4 to +6 seconds per day maximum variation.
Cosmic Ray TestingCertification
Extreme altitude testing verifying chronometer performance stability