nematocyst
noun
nem·a·to·cyst ˈne-mə-tə-ˌsist 
ni-ˈma-tə-
: one of the stinging capsular organelles of the tentacle of a cnidarian (such as a box jellyfish or sea anemone) that contains a coiled, hollow, usually barbed, venomous thread which is discharged especially for catching prey and defending against enemies
Each nematocyst contains a spiral-coiled thread tipped with a toxin-bearing barb that can be ejected into the skin.
Peter F. Weller
Peter F. Wellercalled also cnidocyst
Example Sentences
Recent Examples on the Web Now a team led by Matt Gibson and Ahmet Karabulut of the Stowers Institute for Medical Research in Kansas City, Mo., has used cutting-edge imaging technology to study nematocyst firing in very fine detail. Viviane Callier, Scientific American, 18 Aug. 2022 Using super-resolution fluorescence and electron microscopes, the researchers observed a detailed sequence of events involving a stiff shaft and a flexible, whiplike filament that starts out coiled around it within the nematocyst. Viviane Callier, Scientific American, 18 Aug. 2022 The tentacles contain stinging nematocysts that can deliver venom capable of paralyzing and killing small fish and crustaceans and cause extreme pain and welts to humans. Leada Gore, AL.com, 1 Mar. 2018 The blue dragon steals stinging cells, called nematocysts, from man-of-wars, storing them in specialized organs in the tips of their cerata, or wings—which may explain their name. Liz Langley, National Geographic, 28 Jan. 2017 Researchers initially thought these nematocysts might be genetically similar to those of cnidarians, animals such as jellyfish and sea anemones. Rachel Brown, National Geographic, 5 Apr. 2017 Polykrikos cells have a capsule, called a nematocyst, that contracts to propel a sharp stylet through the water—and through the armor of another microbe. Rachel Brown, National Geographic, 5 Apr. 2017 Some have sharp skeletons and tentacles with nematocysts (stinging cells) that immobilize prey. Bonnie Berkowitz, chicagotribune.com, 30 June 2017 A jellyfish’s tentacles do seem to be an odd choice of meal: humans are wary of their sting, which occurs when skin contact triggers small, harpoon-like structures called nematocysts to inject venoms that attack the victim’s cells. Rachel Brown, National Geographic, 27 June 2017 See More
Viviane Callier, Scientific American, 18 Aug. 2022 Using super-resolution fluorescence and electron microscopes, the researchers observed a detailed sequence of events involving a stiff shaft and a flexible, whiplike filament that starts out coiled around it within the nematocyst. Viviane Callier, Scientific American, 18 Aug. 2022 The tentacles contain stinging nematocysts that can deliver venom capable of paralyzing and killing small fish and crustaceans and cause extreme pain and welts to humans. Leada Gore, AL.com, 1 Mar. 2018 The blue dragon steals stinging cells, called nematocysts, from man-of-wars, storing them in specialized organs in the tips of their cerata, or wings—which may explain their name. Liz Langley, National Geographic, 28 Jan. 2017 Researchers initially thought these nematocysts might be genetically similar to those of cnidarians, animals such as jellyfish and sea anemones. Rachel Brown, National Geographic, 5 Apr. 2017 Polykrikos cells have a capsule, called a nematocyst, that contracts to propel a sharp stylet through the water—and through the armor of another microbe. Rachel Brown, National Geographic, 5 Apr. 2017 Some have sharp skeletons and tentacles with nematocysts (stinging cells) that immobilize prey. Bonnie Berkowitz, chicagotribune.com, 30 June 2017 A jellyfish’s tentacles do seem to be an odd choice of meal: humans are wary of their sting, which occurs when skin contact triggers small, harpoon-like structures called nematocysts to inject venoms that attack the victim’s cells. Rachel Brown, National Geographic, 27 June 2017 See More Word History
Etymology
International Scientific Vocabulary
First Known Use
1862, in the meaning defined above
Medical Definition
nematocyst
noun
nem·a·to·cyst ˈnem-ət-ə-ˌsist ni-ˈmat-ə-
ni-ˈmat-ə- : one of the minute stinging organelles of various coelenterates
called also stinging cell