Dinosaurs in general are named after a trait body aspect, after the place where they were originate, or after a human being involved in the discovery. Generally the name consists of two Greek or Latin words (or grouping); sequentially, these are the genre and the species name. For instance, the Greek and Latin combination (binomen) Tyrannosaurus rex means "king of the tyrant lizards." Biologists name current animals closely the same way. Some examples consist of humans (Homo sapiens), domestic dogs (Canis familiaris), golden eagles (Aquila chrysaetos), box turtles (Terrapene carolina), and rattlesnakes (Crotalus horridus).