worm

noun

Any of various invertebrates, especially an annelid, flatworm, nematode, or nemertean, having a long, flexible, rounded or flattened body, often without obvious appendages.

Any of various crawling insect larvae, such as a grub or a caterpillar, having a soft elongated body.

Any of various other animals, such as a shipworm or a slowworm, having a long slender limbless body.

Something, such as the thread of a screw or the spiral condenser in a still, that resembles a worm in form or appearance.

The spirally threaded shaft of a worm gear.