cog
comb
crag
fang
harrow
jag
peak
pecten
projection
rake
ratchet
sawtooth
snag
snaggle
spire
spur
steeple
toot
tooth
roller
wheel
3/8-inch
axle
bogie
cam
cogwheel
counterweight
crank
detent
diffuser
empennage
fuze
gearbox
idler
linchpin
pinion
pintle
pivot
pulley
reducer
retractable
sheave
spindle
winch
docket
pocket
rocket
socket