crankshaft
nounUK /ˈkræŋkʃɑːft/
US /ˈkræŋkʃæft/
A long metal bar in an engine that turns round and round to make the wheels go.
The mechanic replaced the broken crankshaft in the old car's engine.
OTHER MEANINGS
2. A rod that converts back-and-forth motion into turning motion in a machine.
The pump's crankshaft turned the up-and-down movement into a spinning motion.
3. A person who is bad-tempered or stubborn (informal, rare).
Don't mind old Mr. Grimes; he's a bit of a crankshaft before his morning coffee.
4. A handle bent at a right angle for turning something by hand.
He grabbed the crankshaft and turned it to raise the heavy gate.