chitin

What it means

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

In a sentence

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

Where it comes from

1. Ancient Greekχῐτών (khĭtṓn)
2. Latinchitōn
3. Frenchchitine
4. Englishchitin

From French chitine, from Latin chitōn (“mollusk”), from Ancient Greek χιτών (khitṓn). See also chiton.