chitin

plural chitins

1. countableuncountablebiochemistryA complex polysaccharide, a polymer of N-acetylglucosamine, found in the exoskeletons of arthropods and in the cell walls of fungi; thought to be responsible for some forms of asthma in humans.

   The robot’s energy source is the sugar in the polysaccharide called chitin that makes up a fly’s exoskeleton.

   2004 September 11, New Scientist, page 19

   2 more examples

   Chitin usually occurs throughout Invertebrates in the form of an investment to the outermost cellular layer or ectoderm.

   1880, Arthur Gamgee, A Text-book of the Physiological Chemistry of the Animal Body, Macmillan, page 299

   But this one is the beak of a 120-pound (50-kilogram) giant Humboldt squid and is therefore made of chitin, a much simpler chemical. Chitin is a polymer whose repeating unit, n-acetylglucosamine, is a derivative of glucose (sugar).

   2014, Theodore Gray, photography by Nick Mann, Molecules: The Elements and the Architecture of Everything, 2018 Paperback Edition, page 120

   Synonyms: entomolin