DCT may refer to:
In mathematics:
- Discrete cosine transform, a mathematical transform related to the Fourier transform
- Dominated convergence theorem, a central mathematical theorem in the theory of integration first proposed by Henri Lebesgue
In biology:
- Distal convoluted tubule, a part of the functional unit of the kidney
- Dopachrome tautomerase, a human gene
In business:
- DCT Industrial Trust, from the companies ticker symbol
In computing and technology:
- DCT (videocassette format), a videocassette format developed by Ampex
- Dual clutch transmission, a vehicle technology which allows gears to be selected in fully manual or automatic mode
- Discovery Channel Telescope, a 4.3-meter telescope
- Director Control Tower, the controlling station for guns on a British warship, see British ordnance terms
- Digital cable, Digital Cable Terminal, the generic term for the set-top box required to receive digital cable
- DCT, Digital Core Technology, a baseband generation of Nokia mobile phones
- .dct A proprietary audio file format for digital dictation
On warships:
- Depth charge thrower, a mortar-like weapon used to launch depth charges at targets distant from the ship
- Director Control Tower, a facility equipped to direct and control a ship's gun battery
In entertainment:
- Dreams Come True (band), a Japanese band
- dc Talk, an American Christian band
- DC Thomson a publisher of British comics
In linguistics:
- Discourse-Completion Task, a pragmatics research method
Other:
- Divine command theory, a metaethical theory of morality
- Danescourt railway station, Wales; National Rail station code DCT
- Dennistoun Community Together, a Glasgow community group
- Direct Coombs test, used to test for autoimmune hemolytic anemia.