Sabretooth is a character appearing in American comic books published by Marvel Comics. Created by Chris Claremont and John Byrne, he first appeared in Iron Fist #14 (August 1977) and was initially depicted as a serial killer known as "the Slasher", before being developed into a villain associated with the X-Men during the "Mutant Massacre" crossover in 1986. This portrayal of Sabretooth has endured as the archenemy of the superhero Wolverine.

In his comic book appearances, Sabretooth is the alias of Victor Creed, a psychopathic mutant with enhanced senses, razor-sharp claws, superhuman strength and reflexes, and regenerative healing abilities. There have been various possible accounts of the origin of Sabretooth's feud with Wolverine. The most common story involves both of them being participants of the Weapon X super-soldier program. After Wolverine escapes and attempts to suppress his animalistic qualities, Sabretooth becomes obsessed with forcing Wolverine to embrace his feral instincts by tormenting him and ruining his life.

In the X-Men film series, Sabretooth is depicted as being Wolverine's brother, portrayed by Tyler Mane in X-Men (2000) and Deadpool & Wolverine (2024) and by Liev Schreiber in X-Men Origins: Wolverine (2009). In May 2008, Wizard magazine ranked Sabretooth #193 of the 200 best comic book characters of all time. In 2009, Sabretooth was ranked as IGN's 44th Greatest Comic Book Villain of All Time.

The character first appeared in Iron Fist #14 (August 1977) and was created by Chris Claremont and John Byrne. Sabretooth was conceived as a recurring antagonist for Iron Fist, whom he fights several times, including once hidden behind a mask and gloves as "the Slasher". He works for a time with the Constrictor as a partner-in-crime, and clashes repeatedly with Iron Fist and Power Man. Sabretooth also appeared in comics such as The Spectacular Spider-Man. Chris Claremont introduced him as a minor X-Men villain, a member of the Marauders, during the "Mutant Massacre" crossover in 1986.

Sabretooth rose to greater prominence when he was split off from the Marauders and became a recurring antagonist of an individual member of the X-Men, Wolverine. The character was subsequently featured in limited series and one-shot comics including Sabretooth and Mystique and Sabretooth: In the Red Zone, and even had his own ongoing reprint series in the mid-1990s, Sabretooth Classics.

Chris Claremont intended for Sabretooth to be Wolverine's father, though this was contradicted by subsequent writers. Claremont, when asked what he had intended to be the relationship between Wolverine and Sabretooth, stated:

Father and son. That's why Sabretooth always considered Logan "sloppy seconds" to his "original" / "real deal." The other critical element in my presentation of their relationship was that, in their whole life, Logan has never defeated Sabretooth in a knock-down, drag-out, kill-or-be-killed berserker fight. By the same token, on every one of his birthdays, Sabretooth has always managed to find him, no matter where Logan was or what he was doing, and come within an inch of killing him. For no other reason than to remind him that he could.

Genetic tests performed by S.H.I.E.L.D. confirmed that Sabretooth and Wolverine were not father and son.