PDT may refer to: Computing PHP Development Tools, an IDE plugin for the Eclipse platform PDT Standard Police Digital Trunking, China's police wireless communications standard Portable data terminal, an electronic device that is used to enter or retrieve data via wireless transmission Science and medicine Patient-delivered therapy Photodynamic therapy, treatment for cancer and wet age-related macular degeneration, involving a photosensitizer, light, and tissue oxygen Population doubling time, a number indicating cell growth in cell cultures Pancreaticoduodenal transplantation (see Pancreas transplantation) 1,3-Propanedithiol, an organosulfur compound Business and finance Paramount Domestic Television, United States television series distributor, now CBS Television Distribution Piedmont Airlines (ICAO airline code), an American regional airline PDT Partners, a hedge fund company in New York City that was formerly the trading division of Morgan Stanley Pattern day trader (also Pattern day trading, PDT violation), a stock trader who frequently buys and sells a security within the same trading day Organizations Partido Democrático Trabalhista (Democratic Labour Party), a political party of Brazil Phi Delta Theta, an international fraternity Linguistics Prague Dependency Treebank, a subset of the Czech National Corpus Plautdietsch (ISO 639-3 language code), a Low Prussian variety of East Low German, with Dutch influence Other Please Don't Tell, a cocktail bar in New York City Pacific Daylight Time (UTC−7), daylight saving time in western North America Eastern Oregon Regional Airport (IATA airport code), near Pendleton, Oregon Potentially dangerous taxpayer, an American taxpayer that has demonstrated a capacity for violence against the IRS Peter Dengate Thrush, New Zealand barrister