From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
Planet Makyo (魔凶 惑星, Makyō Wakusei; FUNimation "Makyo Star"; Literally meaning "Demon Evil Planet") is a planet in the North Galaxy.
Planet Makyo appeared during the Garlic Jr. Saga. It was a dark and evil planet and the source of power for all Makyans, especially Garlic Jr. Planet Makyo passed close to Planet Earth once every 12,000 years, coinciding with an alignment of several stars which powered all of the Makyons who inhabited Planet Earth.
It was because of Planet Makyo getting close to Planet Earth that Garlic Jr. was able to escape the Dead Zone. When it got even closer to Planet Earth, Garlic Jr., Spice, and Vinegar were able to buff up and become stronger after being beaten by Piccolo, Kuririn, and Son Gohan. It was extremely close to Planet Earth by the time Garlic Jr. reopened the Dead Zone, but Piccolo knew from Spice that it was Garlic Jr.'s source of power, and so he told Gohan to blow it up. Gohan attacked and destroyed Planet Makyo, draining Garlic Jr.'s energy and causing him to be sucked back into the Dead Zone for all eternity.
- Makyo is the realm of Demons in Japanese Buddhism.