noun Zoology.

an organ of offense and defense embedded in the outer cytoplasm of certain protozoans, consisting of a small elongated sac containing a fine, hairlike filament capable of being ejected.

Origin of trichocyst

First recorded in 1850–55; tricho- + cyst
Related formstrich·o·cyst·ic, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for trichocyst



any of various cavities on the surface of some ciliate protozoans, each containing a sensory thread that can be ejected
Derived Formstrichocystic, adjective
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