any worm of the Chaetognatha; transparent marine worm with horizontal lateral and caudal fins and a row of movable curved spines at each side of the mouth | any of numerous relatively small elongated soft-bodied animals especially of the phyla Annelida and Chaetognatha and Nematoda and Nemertea and Platyhelminthes; also many insect larvae |
| screw thread on a gear with the teeth of a worm wheel or rack |
| a software program capable of reproducing itself that can spread from one computer to the next over a network |
| a person who has a nasty or unethical character undeserving of respect |