What is Pippin Took's full first name?

Peregrin is Pippin Took’s full first name.

Pippin is the familiar form of Peregrin, the name used in formal contexts throughout Tolkien’s history of the Shire. His full name is Peregrin Took, and he is the only son and heir of Paladin Took II, the Thain of the Shire. Pippin’s mother is Eglantine Banks, and he has three older sisters.

Peregrin begins the story as a young, impulsive Hobbit and close companion of Meriadoc Brandybuck, commonly called Merry. At Rivendell, Elrond reluctantly accepts both Hobbits into the Fellowship. Pippin later becomes involved in major events including the awakening of the Balrog in Moria, the defence of Gondor, and the assault on the Black Gate.

After the War of the Ring, Pippin helps lead the resistance during the Scouring of the Shire. He marries Diamond of Long Cleeve, has a son named Faramir, and eventually becomes Thain. Fredegar Bolger, Bandobras Took, and Meriadoc are different Hobbits, not alternative forms of Pippin’s first name.