The Frodo system is a star system somewhere near Alpha Six quadrant.
According to Robber in his conversation with Starbuck, the Frodo system has some "nasty buggers there," and he alleges that "the pirate" came from there (TOS: "The Long Patrol").
Notes
- The existance of the Frodo system is debatable, as it may very well be a fabrication by Robber.
- In literature, Frodo is also the first name of a Hobbit character, Frodo Baggins, in the epic high fantasy book series, The Lord of the Rings. This name may have been used in the series as an homage.