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

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

From Project Gutenberg

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 Project Gutenberg

And by means of a worm gear, operated by a wheel near the steering apparatus, the light could be deflected in any direction.

From Project Gutenberg

The two knobs with drum are mounted on an axle a, which in its central portion is enlarged and provided with a worm gear.

From Project Gutenberg

The rod is attached to the gage with a worm gear and is operated by a small hand wheel at the front of the table.

From Project Gutenberg