GDT may refer to:
Trails Great Dividing Trail, in Victoria, Australia Great Divide Trail, in the Canadian Rocky Mountains
Science and technology Gas discharge tube Gas Dynamic Trap, a Russian magnetic mirror used for fusion power research Geometric dimensioning and tolerancing, GD&T Global Descriptor Table, an x86 data structure Global distance test, to compare proteins Ground Data Terminal GDT or , a medical data format; see xDT
Other uses Ganvsig daighix tongiong pingimv, a romanization system for Taiwanese Minnan Goal-directed therapy, in critical care medicine Grand dictionnaire terminologique, an online terminological database JAGS McCartney International Airport, Turks and Caicos Islands Kungardutyi language MaK GDT, a diesel railbus Guillermo del Toro, director