The Frylon system was a star system inside Federation space in the Alpha or Beta Quadrant. This was a single star system consisting of a primary and at least four planets, including Frylon IV.
The USS Cerritos visited this system in 2381 to investigate reports of a mugato on Frylon IV. After completing the mission, they were leaving the system when Admiral Alonzo Freeman warned Captain Carol Freeman about a scam being run in the local sector, in which a junk ship would purposefully self-destruct and attempt to blame Starfleet so as to obtain compensation. Freeman then realized that she had fallen for such a scam from Hyde. (LD: "Mugato, Gumato")