What is "polyene"

n. (context chemistry English) An organic compound containing several double bonds, especially one containing a sequence of many alternating single and double bonds

Polyenes are poly- unsaturated organic compounds that contain at least three alternating double and single carbon–carbon bonds. These carbon–carbon double bonds interact in a process known as conjugation. Related to polyenes are dienes, where there are only two alternating double and single bonds. Another related class of compounds have three or more double bonds, but they are not alternating with single bonds.