1.
gear, cogwheel, cog
A rotating machine part with teeth that mesh with another toothed part to transmit motion.
2.
cog (in a system)
Figuratively, a small part of a larger mechanism or organization.
Things have started to go wrong within the team, and the project is falling behind.
歯車が狂う = things stop working smoothly
Etymology: 歯 (tooth) + 車 (wheel).
Common patterns
- 歯車が噛み合う (gears mesh - also figurative: things work well together)
- 歯車が狂う (gears go wrong - things stop working smoothly)
- 歯車の一つ (one gear/cog - small part of system)
Usage: Figuratively (sense 2), often used of feeling like an interchangeable part of a large organization or of society: 社会の歯車.
Related Words
Compare:
ギア (gear (of a vehicle))