UDT may refer to: Organisations Uitgeverij De Tijd, a former Belgian publisher Underwater Demolition Team, United States Naval reconnaissance and amphibious landing beach demolition unit from which the U.S. Navy SEALs evolved União Democrática Timorense, (Timorese Democratic Union), a conservative political party in East Timor Union Démocratique Tchadienne, (Chadian Democratic Union), the second African political party in Chad Union of Djibouti Workers, a trade union centre in Djibouti United Dominions Trust, a subsidiary of the former Trustee Savings Bank, merged with Lloyds Bowmaker in 2001 Computing UDP-based Data Transfer Protocol, a high performance data transport protocol and library User-defined type, in computer science that is generally synonymous with "record", "structure", "composite type" or "class" Technology Urine Diversion Toilet, a toilet system where urine and faeces are separated at source