chitin

American

[kahy-tin] / ˈkaɪ tɪn /

noun

Biochemistry.

a nitrogen-containing polysaccharide, related chemically to cellulose, that forms a semitransparent horny substance and is a principal constituent of the exoskeleton, or outer covering, of insects, crustaceans, and arachnids.

chitin British

/ ˈkaɪtɪn /

noun

a polysaccharide that is the principal component of the exoskeletons of arthropods and of the bodies of fungi

"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

chitin Scientific

/ kīt′n /

A tough, semitransparent substance that is the main component of the exoskeletons of arthropods, such as the shells of crustaceans and the outer coverings of insects. Chitin is also found in the cell walls of certain fungi and algae. Chemically, it is a nitrogenous polysaccharide (a carbohydrate).

Other Word Forms

chitinoid adjective
chitinous adjective

Etymology

Origin of chitin

1830–40; < French chitine < Greek chit ( ṓn ) tunic, chiton + French -ine -in ²

Compare meaning

How does chitin compare to similar and commonly confused words? Explore the most common comparisons:

chitin vs. cellulose

Vocabulary lists containing chitin

Biochemistry

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"The Hermit's Story," Vocabulary from the short story

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Microbiology - High School

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

To explore this approach, the researchers removed two genes linked to the enzymes chitin synthase and pyruvate decarboxylase.

From Science Daily • Nov. 21, 2025

Removing the chitin synthase gene resulted in a thinner cell wall, which made the internal protein more accessible for digestion.

From Science Daily • Nov. 21, 2025

These microvilli harbor a specific enzyme that the researches could show to be responsible for the formation of chitin, the material from which the bristles are ultimately made.

From Science Daily • May 13, 2024

How exactly the chitin is formed into distinct bristles has so far remained enigmatic.

From Science Daily • May 13, 2024

Running all through between the two layers of the wing are thickened lines of chitin, which divide and subdivide, forming this fine network.

From Little Busybodies The Life of Crickets, Ants, Bees, Beetles, and Other Busybodies by Marks, Jeannette Augustus

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023