Meaning : A toothed wheel that engages another toothed mechanism in order to change the speed or direction of transmitted motion.
Synonyms : cogwheel, gear wheel, geared wheel
Meaning : Wheelwork consisting of a connected set of rotating gears by which force is transmitted or motion or torque is changed.
Example :
The fool got his tie caught in the geartrain.
Synonyms : gearing, geartrain, power train, train
Meaning : A mechanism for transmitting motion for some specific purpose (as the steering gear of a vehicle).
Synonyms : gear mechanism
Meaning : Equipment consisting of miscellaneous articles needed for a particular operation or sport etc..
Synonyms : appurtenance, paraphernalia