TCDD may refer to:
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Turkish State Railways
The State Railways of the Republic of Turkey (), abbreviated as TCDD, is a government-owned national railway company responsible for the ownership and maintenance of railways in Turkey, as well as the planning and construction of new lines. TCDD ...
(Türkiye Cumhuriyeti Devlet Demiryolları), the national railway carrier of Turkey
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TCDD Taşımacılık
TCDD Transport or Turkish State Railways Transport (, reporting mark TCDDT) is a government-owned railway company responsible for the operations of most passenger and freight rail in Turkey. The company was formed on 14 June 2016, splitting off ...
, a Turkish transport company responsible for railway operations
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2,3,7,8-Tetrachlorodibenzodioxin
2,3,7,8-Tetrachlorodibenzo-''p-''dioxin (TCDD) is a polychlorinated dibenzo''-p-''dioxin (sometimes shortened, though inaccurately, to simply ''dioxin'') with the chemical formula CHClO. Pure TCDD is a colorless solid with no distinguishable ...
, a type of dioxin
{{disambiguation