A worm was any of various elongated, soft-bodied animals that lacked limbs. On Dagobah, there were worms that burrowed into and help aerate soil. Those worms enjoyed soggy earth, which prompted them to surface after rain. On Geonosis, there existed a species of parasitic green worms that could control any organic body, alive or dead, by entering through the nasal cavity. Another parasite, the conduit worm, was known to feed off the electrical wiring of starships. The gargantuan joopa creatures from Seelos were also a type of worm.
- "A Recipe for Death" (Mentioned only)
- Star Wars: The Clone Wars – "Legacy of Terror" (First appearance)
- Star Wars: The Clone Wars – "Brain Invaders"
- Star Wars: The Clone Wars – "Missing in Action" (Mentioned only)
- Servants of the Empire: Edge of the Galaxy (Mentioned only)
- Star Wars Rebels – "The Lost Commanders"
- Star Wars Rebels – "Relics of the Old Republic" (Carcass only)
- Star Wars Battlefront
- Heir to the Jedi (Mentioned only)
- The Empire Strikes Back: So You Want to Be a Jedi? (Mentioned only)
- Aftermath: Life Debt (Mentioned only)
- "The Crimson Corsair and the Lost Treasure of Count Dooku"
- Star Wars: The Force Awakens: A Junior Novel (Mentioned only)