Technical language should make a watch easier to evaluate—not harder. These definitions describe watchmaking concepts and do not validate any specific seller's claims.
Amplitude
Angular swing of the balance, generally estimated with a timegrapher; interpretation depends on movement and test conditions.
Beat error
The difference in timing between the balance's alternating beats, as reported by a timegrapher.
Calibre
The identifying designation for a movement design or family.
Chronograph
A watch complication that times intervals, normally using start, stop and reset controls.
Clone movement
Marketing terminology for a mechanism intended to resemble another calibre; the term alone does not prove identical function or parts.
Homage
General description for a design influenced by another; legality depends on actual branding and intellectual-property rights.
Power reserve
How long a watch can run from a given winding state without additional energy input.
QC
Quality control: a collection of checks against specified acceptance criteria.
904L
High-alloy austenitic stainless steel designation. Material identity requires evidence beyond a product listing.
Water resistance
Resistance to water under defined test conditions; cannot be established by appearance alone.