Flatliner may refer to:
A person whose brain or cardiac activity is measured as a flatline The Flatliners, a Canadian ska punk rock band 4-Methylthioamphetamine, a psychoactive drug Flatliners, a 1990 science fiction psychological horror film directed by Joel Schumacher Flatliners (2017 film), a 2017 remake of the 1990 film, directed by Niels Arden Oplev "Flatliner" (song), a song by Cole Swindell and Dierks Bentley Another name for the Reverse STO, a professional wrestling move Flatlinerz, a band
See also Flatline (disambiguation)