William Glenn Shadix (April 15, 1952 - September 7, 2010), known professionally as Glenn Shadix, was an American actor, known for his role as Otho Fenlock in Tim Burton's horror/comedy film Beetlejuice.

For Disney, he provided the voice of the Mayor of Halloween Town in The Nightmare Before ChristmasRay Gherkin in the Dinosaurs episode "Scent of a Reptile", a Monster in the Dinosaurs episode "Driving Miss Ethyl" and Dr. Emile Crocker in the Quack Pack episode, Pardon My Molecules. He also portrayed Chet in The Parent Trap IV: Hawaiian Honeymoon.