Olive cut- cut the inner ring of ruby drilling bearing into a slightly convex shape. Motherboard-commonly known as splint-is the support of watch core, with holes and grooves, which is used to place various parts.

Mainspring-mainspring

master clock

Master works-the title of master craftsman.

Average/contribution time-average or ordinary time.

Mechanical motion-mechanical motion

Mechanical watch-mechanical watch

Mineral crystal-mineral crystal

Three rivers table in minute repeater

Moon phase and January phase

Mother of pearl-mother of pearl

Lacour lacquer

Lever-the anchoring escapement component connecting the balance wheel and the escapement wheel, commonly known as messenger.

LIGNE is a traditional unit for measuring the caliber of a movement.

Limited edition-limited edition

Lug-ear

Kinetic energy-power storage mechanism

Pallet escapement mechanism

perpetual calendar

Pinion-a part installed in the center of the gear shaft.

As soon as the pivot rotates in the jewel bearing,

Plate-machine plate, used to fix the bridge of the watch and the metal plate of various parts.

Platinum-platinum

Pocket watch-pocket watch, pocket watch

Pointer calendar single pointer calendar

Polishing once

Power reserve-power reserve

Power reserve/up-down indicator

On the "up/down" arc scale on the surface, the pointer indicates the relaxed state of the spring.

Displays the number of hours that can still be run.

Printed circuit-printed circuit

A method for connecting different components in an integrated electronic timepiece, such as a timer, a power supply and even an integrated circuit.

Pulse timer

PVD vapor deposition method

Observatory Timing Competition-Observatory Timing Competition