nematocyst Zool.
(ˈnɛmətəsɪst)
[f. nemato- + cyst.]
A small cell in the external layer of jelly-fishes and other cœlenterates, containing a thread capable of being ejected and of producing a stinging sensation; a lasso-cell or thread-cell.
| 1875 Huxley in Encycl. Brit. I. 129/1 The Actinozoa agree with the Hydrozoa..in possessing thread cells, or nematocysts. 1877 ― Anat. Inv. Anim. iii. 124 In its most perfect form, a nematocyst is an elastic thick-walled sac, coiled up in the interior of which is a long filament, often serrated or provided with spines. 1888 Rolleston & Jackson Anim. Life 781 The tentacles especially are provided with nematocysts of two sizes. |