Find the word definition

Wiktionary
cycloheptene

n. (context organic compound English) The unsaturated alicyclic hydrocarbon containing seven carbon atoms and one double bond; any derivative of this compound

Wikipedia
Cycloheptene

Cycloheptene is a 7-membered cycloalkene with a flash point of -6.7 °C. It is a raw material in organic chemistry and a monomer in polymer synthesis. Cycloheptene can exist as either the cis- or the trans-isomer.

:{| | | |- | align ="center"|cis-Cycloheptene | align ="center"|trans-Cycloheptene |}