Watch Glossary: Every Term Defined

The Collector's Reference

A comprehensive glossary of every watch term you will encounter. Keep this handy.

Movement Terms

• NH35: Seiko automatic, 3-hand date
• NH34: Seiko automatic, GMT
• VK63: Seiko mecha-quartz chronograph
• Beat rate: oscillation frequency
• Power reserve: runtime after full wind
• Amplitude: balance wheel swing distance

Case Terms

• Lug-to-lug: total height from tip to tip
• Diameter: width across dial
• Thickness: height from caseback to crystal
• Lug width: strap attachment width

Quality Terms

• Applied indices: physical markers — premium
• AR coating: anti-reflective — improves clarity
• Screw-down crown: compresses gasket
• COSC: Swiss accuracy certification

Frequently Asked Questions

What does "in-house" mean?
Movement designed and manufactured by the brand itself.

What is "Swiss Made"?
See our Swiss Made guide.