What does wormgear mean?
Worm gear is a mechanical transmission in which a rotating, screw-like worm meshes with the teeth of a wheel. Because the worm advances by only a small amount for each turn, the arrangement usually reduces speed while greatly increasing torque, making it useful in gearboxes, conveyors, machine tools, and other equipment requiring controlled, compact power transmission. The name can refer either to the toothed wheel that engages the worm or, more broadly, to the worm-and-wheel assembly, depending on context. It is a technical term rather than everyday vocabulary and is typically written as an open compound, although “worm-gear” is common when it modifies another noun, as in “worm-gear drive.” Despite its unusual name, the mechanism applies the same basic principle as a screw and nut: rotational motion is converted into slow, powerful motion with a substantial reduction in speed.
nounA mechanical transmission in which a rotating, screw-threaded worm meshes with the teeth of a wheel. It usually reduces speed while increasing torque and is commonly used in gearboxes and heavy machinery.
- A worm-and-wheel transmission that changes rotational speed and torque, usually between perpendicular axes.
- The toothed wheel component that meshes with a rotating worm and is driven by it.
"The winch uses a worm gear to trade speed for torque."
"The lathe was fitted with a worm gear to reduce the speed of the cutting spindle."
"A worn tooth on the worm gear was responsible for the unusual noise."
The standard plural of the open compound noun; the hyphenated form “worm-gears” is occasionally encountered in technical writing.
"Several worm gears are used to coordinate the conveyor belts."
A machine's “worm” is not a creature at all—it is a screw that turns a toothed wheel.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of wormgear
Worm gear is an English compound formed from “worm” and “gear.” In this mechanical sense, “worm” denotes a rotating screw-like part, while “gear” comes through Middle English from Old Norse gjárv, meaning equipment or gearing. The “worm” element ultimately derives from Old English wyrm; Latin vermis, reflected in English words such as vermiculate and vermivorous, is commonly traced to the same Indo-European root.
Related word forms
How wormgear is actually used
This is principally a mechanical-engineering term. The open compound “worm gear” is standard in general prose, while “worm-gear” is common when the term modifies another noun, as in “worm-gear drive.” Depending on context, the phrase may denote either the complete transmission or its toothed-wheel component.