In James Cameron’s 2009 film Avatar, the former Marine is named Jake Sully.
Jake Sully is the film’s central human character. After his twin brother, Tommy Sully, dies, Jake is recruited to replace him in the Avatar Program because he shares the genetic profile needed to operate Tommy’s avatar body.
Jake travels to Pandora and becomes involved with the Na’vi, particularly Neytiri and the Omaticaya clan. His experiences lead him to question the RDA’s mission and the treatment of Pandora’s inhabitants. The name “Jake” is his first name; “Sully” is his family name.
The character is played by Sam Worthington. His role is sometimes described simply as “the Avatar,” but Avatar is the film’s title and the name of the engineered Na’vi-like body, not Jake’s personal name.