pneumatocyst


pneu•mat•o•phore

(nʊˈmæt əˌfɔr, -ˌfoʊr, nyʊ-)

n. 1. a specialized structure developed from the root in certain plants growing in swamps and marshes, serving as a respiratory organ. 2. the air sac of a siphonophore, serving as a float. [1855–60] pneu•ma•toph•or•ous (ˌnu məˈtɒf ər əs, ˌnyu-) adj.