driving wheel

American  

noun

1. Machinery. a main wheel that communicates motion to others.

2. Also called driver.  Railroads. one of the wheels of a locomotive that transmits the power of an engine or motor into tractive effort.

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driving wheel British  

noun

1. a wheel, esp a gear wheel, that causes other wheels to rotate

2. any wheel of a vehicle that transforms torque into a tractive force

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Etymology

Origin of driving wheel

First recorded in 1830–40

Example Sentences

Anyone who knows me will tell you that I’m so clumsy, I should be nowhere near the driving wheel of a vehicle or the on-button of a power tool.

From The Guardian • Sep. 16, 2019

As this happens, throw your weight to the high side of the machine to keep the driving wheel in good contact with the bottom of the bog.

From Time Magazine Archive

And at length Mr. Rochester edges aside, and lets him take the driving wheel.

From Sea and Sardinia by Lawrence, D. H. (David Herbert)

The movable hour circle and driving wheel of the Crossley reflector has two sets of graduations.

From Photographs of Nebul? and Clusters Made with the Crossley Reflector by Keeler, James Edward

There's three of the steel studs worn close down on the off driving wheel, which makes a queer little mark in dust or mud.

From The Car of Destiny by Both, Armand