The Goa'uld (pronounced ; commonly shortened to or ) are a symbiotic race of ancient astronauts from the American-Canadian military science fiction television franchise Stargate. The Goa'uld are parasites from the planet P3X-888, integrated within a host, most of the time a human. The resulting creatures are a powerful race bent on galactic conquest and domination, largely without pity, compassion or remorse. In the first eight seasons of Stargate SG-1, they are the greatest extraterrestrial threat to Earth known to the Stargate Command (SGC). The Goa'uld are the main enemies of SG-1 for most of the show, until they are replaced in this capacity by the Ori in seasons 9 and 10. They also appear in the Stargate Atlantis episode , and in the DVD movie . They are pejoratively called "snakes" or "snakeheads" by Jack O'Neill.