gear; cogwheel
A toothed wheel that transmits motion or power in a machine.
時計の歯車が壊れて動かなくなった。
The clock's gears broke and it stopped working.
The gears mesh and the machine starts moving.
cog in a machine; small part of a system
Metaphorical use for a person or element that is a small, functional part of a larger organization or system.
大企業では、一人ひとりが歯車の一部に過ぎないと感じることがある。
In a large corporation, one sometimes feels like just a cog in the machine.
組織の歯車として働くことに誇りを持っている。
I take pride in working as a cog in the organization.
I tried turning the machine's gear by hand.
When I flipped the switch, the gears started turning.
He felt doubts about becoming just a cog in a large organization.
sun gear; sun wheel
differential gear