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tetracyanoethylene

n. (context organic compound English) The unsaturated nitrile (N≡C)2C=C(C≡N)2 used in the manufacture of dyes

Wikipedia
Tetracyanoethylene

Tetracyanoethylene (TCNE), more correctly ethenetetracarbonitrile, is a clear colored organic compound consisting of ethylene with the four hydrogen atom replaced with cyano groups. It is an important member of the cyanocarbons.