The Collaborative International Dictionary
Nematocyst \Nem"a*to*cyst\, n. [Nemato- + cyst.] (Zo["o]l.) A lasso cell, or thread cell. See Lasso cell, under Lasso.
Douglas Harper's Etymology Dictionary
Wiktionary
n. (context biology English) A capsule, in certain cnidarians, containing a barbed, threadlike tube that delivers a paralyzing sting
Wikipedia
A nematocyst is a subcellular structure or organelle containing extrusive filaments found in two families of athecate dinoflagellates (a group of unicellular eukaryotes), the Warnowiaceae and Polykrikaceae. It is distinct from the similar subcellular structures found in the cnidocyte cells of cnidarians, a group of multicellular organisms including jellyfish and corals; such structures are also often called nematocysts (alternatively, cnidocysts or cnidae), and cnidocytes are sometimes referred to as nematocytes. It is unclear whether the relationship between dinoflagellate and cnidarian nematocysts is a case of convergent evolution or common descent, although molecular evidence has been interpreted as supporting an endosymbiotic origin for cnidarian nematocysts.
In polykrikoids the nematocyst is found associated with another extrusive organelle called the taeniocyst, a complex that has been described as synapomorphic for the genus Polykrikos.
The full range of functional roles of the nematocyst is not well understood, but it has been observed to be involved in prey capture and feeding.
Usage examples of "nematocyst".
Boris winces momentarily as the nematocysts let rip inside his mouth, but in a moment or so, the cubozoan slips down, and in the meantime, his biophysics model clips the extent of the damage to his stinger-ruptured oropharynx.
The ixchitl, pre-Fall, had not had poisonous nematocysts, so that was probably one of her little "tweaks.
His ability to avoid the stinging nematocysts while manipulating the jellyfish never ceased to astound her.
Its nematocysts burned the cavity of my chest and seared the length of my left arm.