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semiochemical

British  
/ ˌsɛmɪəʊˈkɛmɪkəl /

noun

  1. a chemical substance produced by an animal and used in communications, such as a pheromone

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of semiochemical

C20: semio- from Greek sēmeion a sign + chemical