John Constantine Flippen Jr. (J.C. or Jay C.) (March 6, 1899 – February 3, 1971) was an American character actor who often played crusty sergeants, police officers or weary criminals in many 1940s and 1950s pictures, particularly in film noir.

He began performing as a standup comedian in burlesque, vaudeville and minstrel shows, which made him a natural in obtaining roles in occasional slapstick and light musical comedy.

When the Broadway stage revue Hellzapoppin became a success, its stars Olsen and Johnson decided to send the show on tour while they were playing it in New York.

Flippen played a number of memorable roles in film noir, notably as one of the gang members in Stanley Kubrick's 1956 ensemble thriller The Killing.

He appeared on television, including a 1960 guest-starring role as Gabe Jethrow in the episode "Four Came Quietly" on the CBS Western series Johnny Ringo, starring Don Durant.

In the 1962–63 season, Flippen was cast as Chief Petty Officer Homer Nelson on the NBC sitcom Ensign O'Toole, with Dean Jones in the starring role.

After a leg amputation in 1965, Flippen continued acting, usually using a wheelchair, such as in his comeback role in a 1966 episode of The Virginian and his 1967 guest appearance in Ironside (season one, "A Very Cool Hot Car").

While filming Cat Ballou in 1965, he had to have a leg amputated due to a serious infection, originally resulting from a minor scrape with a car door, and likely complicated by diabetes.