Abbott and Costello (William "Bud" Abbott, 1895-1974, and Lou Costello, 1906-1959) were an American comedy team who were popular during the 1940s and 1950s, and best known for their comedy routine, "Who's on First?" Abbott served as the devious straight man, and Costello as the stumbling, dimwitted laugh-getter, who would often draw out his signature call, "HEY, ABBOTT!" The pair achieved success on stage (mostly burlesque but also vaudeville), in films, on radio (where their verbal routines were particularly well-suited), and television.
- In a "Theater in the Park" sketch, Telly Monster (as Romeo) yells for Alphabet in the distinct stylings of Costello calling for Abbott.
- Ernie's breathy gasps as he relates to Bert, "the staaa, the staaa-tue", in a sketch where the duo travel to Egypt, is inspired by Costello's frightened reaction in Abbott and Costello Meet Frankenstein and other films.
- In episode 422 of The Muppet Show, during the Veterinarian's Hospital sketch, Miss Piggy comments that since they have a rabbit for a patient, the jokes are like "Rabbit and Costello".
- In The Muppets Go Hollywood, Dick van Dyke catches Fozzie Bear in front of Grauman's Chinese Theatre with a bag of cement, planning to add his own signature in the cement next to Abbott and Costello, the Marx Brothers and the Ritz Brothers.
- Footage of Abbott and Costello Meet Frankenstein (1948) appears in the Muppet Babies episode "Remote Control Cornballs," specifically scenes of Bela Lugosi
- Footage of Abbott and Costello themselves, from Africa Screams (1949), appears in the Muppet Babies episode "At the Movies." Baby Bean Bunny, trying to find Bambi, wanders into a theater screen playing the movie, a scene where Abbott and Costello are paddling a boat in the jungle. Costello discovers an alligator and, with an eggbeater, makes a quick getaway. Later in the same episode, Bean befriends the movie's gorilla suited simian (redubbed by Frank Welker).
- "Boogie Woogie Bugle Boy," from the Abbott and Costello film Buck Privates, is performed in the Dinosaurs episode "Nuts to War (part 2)."
- In The Wubbulous World of Dr. Seuss episode "Horton Has a Hit", The Fox in Socks and Mr. Knox are shown having their own variety show. One scene shows them performing a "Who's On First?" routine, but with the name "Cindy Lou Who."
- In a DXD video, Kermit and Fozzie share an exchange about Whatnots resulting in a similar word play present in Abbott and Costello's "Who's On First?" sketch. Toward the end, a frustrated Fozzie even breaks the flow to interject with "third base!"
- In part 4 of The Muppet Show Comic Book: Muppet Mash, Statler and Waldorf have a "Who's on First?"-style exchange, with Waldorf being confused about a Poob named Hugh.