nematocyst

[nem-uh-tuh-sist, ni-mat-uh-]

noun Zoology.

an organ in coelenterates consisting of a minute capsule containing an ejectable thread that causes a sting.

Origin of nematocyst

First recorded in 1870–75; nemato- + -cyst

Related formsnem·a·to·cys·tic, adjective

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

Examples from the Web for nematocyst

Historical Examples of nematocyst

The cnidoblasts are the mother-cells of the nematocysts, each cell producing one nematocyst in its interior.
Encyclopaedia Britannica, 11th Edition, Volume 14, Slice 2
Various

British Dictionary definitions for nematocyst

nematocyst

noun

a structure in coelenterates, such as jellyfish, consisting of a capsule containing a hollow coiled thread that can be everted to sting or paralyse prey and enemies

Derived Formsnematocystic, adjective

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 nematocyst

1875, from nemato-, comb. form of Greek nema, nematos "thread" (genitive nematos), from stem of nein "to spin" (see needle (n.)) + cyst.

nematocyst in Medicine

nematocyst

[nĕm′ə-tə-sĭst′, nə-măt′ə-]

n.

A capsule within specialized cells of certain coelenterates containing a barbed, threadlike tube that delivers a paralyzing sting.

nematocyst in Science

nematocyst

[nĕm′ə-tə-sĭst′, nĭ-măt′ə-sĭst′]

One of the minute capsules in the tentacles of cnidarians, such as jellyfish, hydras, or sea anemones, used for stinging. The capsule is produced by a special cell (called a cnidoblast) and contains a tightly coiled barbed thread that quickly shoots forth if the capsule's lid is disturbed. The thread often contains poison.