TDT

TDT may refer to:
 * Digital terrestrial television
 * TDT (TV station), a digital television station in Tasmania, Australia
 * TDT (Portugal), digital terrestrial television in Portugal
 * TDT (Spain), digital terrestrial television in Spain
 * TDT Band (The Down Troddence), a six piece Indian thrash metal band
 * TDT Banda or Thamar Dillon Thomas Banda (fl. 1957–1962), Nyasaland politician
 * Terminal deoxynucleotidyl transferase, a specialized DNA polymerase expressed in immune cells
 * Terrestrial Dynamical Time, an obsolete name for Terrestrial Time
 * The Damned Things, an American heavy metal supergroup
 * Time domain transmissometry, a method of testing transmission lines
 * Toronto Dance Theatre, a Canadian modern dance company based in Toronto, Ontario
 * Tracing Debugging Technique, an early debugger by DEC
 * Transmission disequilibrium test, a family-based genetic association test
 * The Dark Tower (series), a book series written by Stephen King.