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

  1. 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

Other words from nematocyst

  • nem·a·to·cys·tic, adjective

Words Nearby nematocyst Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use nematocyst in a sentence

British Dictionary definitions for nematocyst


/ (ˈnɛmətəˌsɪst, nɪˈmætə-) /

  1. 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 forms of nematocyst

  • nematocystic, 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

Scientific definitions for nematocyst


[ nĕmə-tə-sĭst′, nĭ-mătə-sĭst′ ]

  1. 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.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.