Pneumatocyst
Pronunciation : Pneu*mat"o*cyst
Part of Speech : n.
Etymology : [Pneumato- + cyst.] (Zo?l.)
Definition : Defn: A cyst or sac of a siphonophore, containing air, and serving as a float, as in Physalia.
Source : Webster's Unabridged Dictionary, 1913
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