Definify.com
Webster 1913 Edition
Pneumatocyst
Pneu-mat′o-cyst
,Noun.
[
Pneumato-
+ cyst
.] (Zool.)
A cyst or sac of a siphonophore, containing air, and serving as a float, as in Physalia.
Definition 2024
pneumatocyst
pneumatocyst
English
Noun
pneumatocyst (plural pneumatocysts)
- (marine biology) A sac or other structure containing air and used for flotation by a marine organism, chiefly used in reference to those of kelps and siphonophores.