US Popularity Rank: 1480

Origin: Latin

Meaning: King

Rex is a boy’s name of Latin origin. Meaning “king,” this regal name is more likely to spring images of dinosaurs to mind than the monarchy. Rex is commonly used in the title T-Rex—the carnivorous predators that once roamed North America. Aspiring archaeologists and die-hard fans of Jurassic Park will be drawn to Rex as a baby name, both for its connections to prehistoric creatures and its majestic meaning.