A lubricant was a substance used to lower the friction between two surfaces.
- Darth Plagueis
- The New Jedi Order: Agents of Chaos II: Jedi Eclipse
- Jedi Apprentice: The Rising Force
- "Ringers"—Star Wars Adventure Journal 6
- Death Star
- Star Wars 12: Doomworld!
- Splinter of the Mind's Eye (Mentioned only)
- Splinter of the Mind's Eye 1 (Mentioned only)