DET

DET or Det may refer to:
 * A common abbreviation of the U.S. city of Detroit and its major professional sports teams.
 * Detroit Lions of the National Football League
 * Detroit Pistons of the National Basketball Association
 * Detroit Tigers of Major League Baseball
 * Detroit Red Wings of the National Hockey League
 * Detroit (Amtrak station), station code
 * Duolingo English Test (DET), a standardized test of English language
 * Coleman A. Young International Airport, Detroit, US, IATA Code
 * Diethyltryptamine, a psychedelic drug
 * Detection error tradeoff
 * It (Christensen book) (Det in Danish), poetry book
 * The mathematical determinant
 * Department of Education (New South Wales), formerly the Department of Education and Training (DET)
 * 14 Intelligence Company, UK military undercover unit
 * a determiner, in interlinear glossing