/sist/ , n.
1. Pathol. a closed, bladderlike sac formed in animal tissues, containing fluid or semifluid matter.
2. a bladder, sac, or vesicle.
3. Bot. , Mycol.
a. a sporelike cell with a resistant, protective wall.
b. a cell or cavity enclosing reproductive bodies.
4. Zool.
a. a sac, usually spherical, surrounding an animal that has passed into a dormant condition.
b. such a sac plus the contained animal.
c. a capsule or resistant covering.
[ 1705-15; cystis kýstis bag, pouch, the bladder; akin to kyma CYMA ]