2 definitions found

From WordNet (r) 2.0 [wn]:

chitin

noun: a tough semitransparent horny substance; the principal component of the exoskeletons of arthropods and the cell walls of certain fungi

From The Collaborative International Dictionary of English v.0.44 [gcide]:

Chitin \Chi"tin\, noun [See {Chiton}.] (Chem.) A white amorphous horny substance forming the harder part of the outer integument of insects, crustacea, and various other invertebrates; entomolin.
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