actuator
auto
break
changer
cogged
cogwheel
commutator
corrode
corrosion
corrosive
driver
engine
forks
fret
gas
gear
gearbox
gearwheel
helical
industrial
industry
iron
jagged
motion
motor
mover
oil
orbit
pinion
play
power
rack
revolution
rotary
rotate
running
rust
shaft
shifter
speed
steel
switch
toothed
torque
transmission
turn
wheeled
wicket