worm gear

American  

Or wormgear

noun

1. a mechanism consisting of a worm engaging with and driving a worm wheel, the two axes usually being at right angles, used where a relatively low speed and a relatively large amplification of power are desired.

2. Also called worm wheel.  a gear wheel driven by a worm.

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worm gear British  

noun

1. a device consisting of a threaded shaft ( worm ) that mates with a gearwheel ( worm wheel ) so that rotary motion can be transferred between two shafts at right angles to each other

2. Also called: worm wheel.  a gearwheel driven by a threaded shaft or worm

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Etymology

Origin of worm gear

First recorded in 1875–80

Example Sentences

Probably he saw me enter, but how could he know enough to work the worm gear and close the door?

From Tom Swift and His Submarine Boat, or, under the Ocean for Sunken Treasure by Appleton, Victor [pseud.]

The ensign merely nodded and began to operate a worm gear which swung the tubes at an acuter angle to the body of the submarine vessel.

From The Boy Scouts for Uncle Sam by Goldfrap, John Henry

These have a speed reduction from armature shaft to bridge column of 1500 to 1, through four intermediate spur gears and a worm gear.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Part 3 "Brescia" to "Bulgaria" by Various

The motion obtained from the worm gear is transferred through suitable gearing to the rack pinion.

From Modern Machine-Shop Practice, Volumes I and II by Rose, Joshua

The chain drive also allows the replacement of the sprocket with one of a larger or smaller diameter thereby giving a higher or lower gear ratio, which cannot be done with the worm gear.

From Motor Truck Logging Methods Engineering Experiment Station Series, Bulletin No. 12 by Knapp, Frederick Malcolm