▪ I. cyst
(sɪst)
Also 8 cist.
[ad. mod.L. cystis (in earlier use: see cystis): in mod.F. kyste.]
1. Biol. A thin-walled hollow organ or cavity in an animal body (or plant) containing a liquid secretion; a bladder, sac, vesicle.
| c 1720 W. Gibson Farrier's Dispens. ii. i. (1734) 36 Under their [vipers'] tongue is a little Cyst or bag where the poison is deposited. 1796 Morse Amer. Geog. I. 228 The Ink or Cuttle fish..is furnished with a cyst of black liquor. 1866 Treas. Bot., Cyst..the hollow spaces in parenchyma in which oily matter collects, as in the rind of the orange. |
2. Path. A closed cavity or sac of a morbid or abnormal character, containing liquid or semi-solid matter.
| 1731–1800 Bailey, Cist..a Tumour where the obstructed Matter collects as in a Bag. 1807–26 S. Cooper First Lines Surg. (ed. 5) 25 In abscesses of long standing, the cysts are often of very considerable thickness. |
| fig. 1884 Jaunt in a Junk 71 As it were, form an indelible cyst of penal associations round the very idea. |
b. spec. The sac enclosing a hydatid, or larval form of a species of Tænia or tape-worm, found parasitic in man and various other animals. (Cf. acephalocyst.)
| 1713 Cheselden Anat. (1726) 181 The liver full of hydatids, and cysts of hydatids adhering to it. 1888 Rolleston & Jackson Anim. Life 231 The cyst in which the Cysticercus lies is formed by the irritated tissues of its host. |
3. Biol. and Cryptogamic Bot. A cell or cavity containing reproductive bodies, embryos, etc.; e.g. the spore-case of certain fungi.
| 1857 Berkeley Cryptog. Bot. 134 Müller informs us that in C. tuberculosa, he has repeatedly seen two kinds of cysts, one scarlet, and constituting antheridia, the other larger and at length producing spores. 1867 J. Hogg Microsc. ii. i. 263 They occasionally develop an enveloping cyst and thus become encysted zoospores. |
4. Comb., as cyst-fluid, cyst-wall, cyst-worm; also cyst-like a.
| 1836–39 Todd Cycl. Anat. II. 220/2 Cyst-like tumours. 1847–9 Ibid. IV. 95/2 Atrophy of the renal textures dependent on cyst-formation. 1871 Holmes Syst. Surg. (ed. 2) V. 917 The cyst-worms of one animal give rise to tape⁓worms in another and vice-versa. |
▪ II. cyst
obs. form of cist.