chitin

[ 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.

Nearby words

Origin of chitin

1830–40; < French chitine < Greek chit(ṓn) tunic, chiton + French -ine -in²

Related formschi·tin·ous, chi·tin·oid, adjective

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for chitinous

The outer layer is contained in a chitinous membrane which spreads out over the base of the sponge.
Freshwater Sponges, Hydroids & Polyzoa|Nelson Annandale
The testis is single, and its duct opens into the intestine and is provided with two chitinous spicules.
Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 2|Various
On this distended receptacle appear several darker plates; these are the remains of the chitinous parts of the primitive wings.
The Industries of Animals|Frdric Houssay
They are strong, recurved, chitinous, structures which prop up the body of the larva when it creeps and wriggles.
The Flea|Harold Russell

The chitinous shell is hyaline and plastic to a slight extent, so that the body is capable of some change in shape.
Marine Protozoa from Woods Hole|Gary N. Calkins

British Dictionary definitions for chitinous

chitin

/ (ˈkaɪtɪn) /

noun

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

Derived Formschitinous, adjectivechitinoid, adjective

Word Origin for chitin

C19: from French chitine, from Greek khitōn chiton + -in

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

Word Origin and History for chitinous

chitin

1836, from French chitine, from Greek khiton "frock, tunic," of soldiers, "coat of mail," used metaphorically for "any coat or covering." "Probably an Oriental word" [Liddell & Scott]. Klein compares Hebrew kuttoneth, Aramaic kittana, Arabic kattan "linen."

Medicine definitions for chitinous

chitin

[ kīt′n ]

n.

A tough, protective, semitransparent polysaccharide forming the principal component of arthropod exoskeletons and the cell walls of certain fungi.

Related formschi′tin•ous adj.

Science definitions for chitinous

chitin

[ 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).