• WordNet 3.6
    • n pneumatophore an air-filled root (submerged or exposed) that can function as a respiratory organ of a marsh or swamp plant
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Webster's Revised Unabridged Dictionary
    • n Pneumatophore (Zoöl) One of the Pneumonophora.
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Century Dictionary and Cyclopedia
    • n pneumatophore A pneumatocyst, or a structure which supports such a float; especially, the proximal dilatation of the cœnosarc or hydrosome of the Physophoridæ See cuts under Athorybia and Hydroszoa.
    • n pneumatophore An apparatus for supplying a person with oxygen when in a place filled with bad or unwholesome air. It consists of a breathing-bag containing alkali in solid form to absorb the carbonic acid gas breathed out of the lungs, and two steel cylinders filled with oxygen at a pressure of about 1,800 pounds per square inch. The apparatus is used principally for entering coal-mines after explosions. Also pneumatophor.
    • n pneumatophore In phytogeography, a lateral root, submerged or more often exposed to the air, at least periodically, so differentiated as to serve the purpose of respiration; a respiratory root. In submerged pneumatophores the aerating tissue often consists of aërenchyma; in projecting pneumatophores it consists of air-containing cork or cortex. Projecting pneumatophores assume an upright position, due to negative geotropism. An example is presented by the knees of the bald cypress. See knee, 3 .
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Webster's Revised Unabridged Dictionary
Pneumato-, + Gr. fe`rein to bear


In literature:

Divergent views have been held as to the morphological significance of the pneumatophore.
"Encyclopaedia Britannica, 11th Edition, Volume 14, Slice 2" by Various