gearbox

/ˈɡɪrˌbɑks/
noun
  1. A metal case that contains the gears of a vehicle or machine, especially the part of a car that changes the speed of the wheels.
    • The factory uses a heavy-duty gearbox to control the speed of the conveyor belt.
    • My dad's old truck has a manual gearbox that makes a loud whining noise in third gear.
    • The mechanic had to remove the entire gearbox to fix the broken gear.
Synonyms
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