What was Peter Pettigrew's nickname in the Marauders?

Wormtail is correct because Peter Pettigrew’s Animagus form is a rat, and his Marauder nickname reflects that “wormy,” skinny tail. Among the Marauders—James Potter (Prongs), Sirius Black (Padfoot), Remus Lupin (Moony), and Peter (Wormtail)—each name ties to their animal or condition. They even created the Marauder’s Map and became illegal Animagi to support Lupin during full moons. Helpful context: “Snivellus” was a cruel nickname for Severus Snape, “Padfoot” (not Footpad) is Sirius, and “Moonrunner” isn’t canon—Remus is “Moony.” Memory tip: think tails—Prongs has antlers, Padfoot has paws, Moony howls at the moon, and the rat’s thin, worm-like tail makes Peter “Wormtail.”