What is the name of the wolf who is foiled by Sam Sheepdog?

The wolf repeatedly foiled by Sam Sheepdog is Ralph Wolf.

Ralph and Sam are the working-class rivals at the center of a series of Warner Bros. cartoons created by Chuck Jones and writer Michael Maltese. Ralph tries to steal sheep during the workday, while Sam guards the flock and routinely stops him with remarkable ease.

Their first starring short was “Don’t Give Up the Sheep,” released in 1953. The cartoons turn the usual predator-versus-guardian chase into an office-comedy routine: Ralph and Sam arrive with lunch pails, punch the same time clock, perform their opposing jobs, and often leave as friendly coworkers when the whistle blows.

Ralph’s appearance causes one of the most common Looney Tunes mix-ups. He closely resembles Wile E. Coyote because both characters were designed in Chuck Jones’s studio style and use similar body shapes and Acme products. Ralph is nevertheless a distinct character: he hunts sheep rather than roadrunners and treats the pursuit as a job rather than an all-consuming obsession. Early cartoons also use names inconsistently, but Ralph Wolf is the canonical name for Sam’s recurring opponent.