|1.||a specialized root of certain swamp plants, such as the mangrove, that branches upwards, rising above ground, and undergoes gaseous exchange with the atmosphere|
|2.||a polyp in coelenterates of the order Siphonophora, such as the Portuguese man-of-war, that is specialized as a float|
|pneumatophore (n-māt'ə-fôr', n'mə-tə-) Pronunciation Key
A specialized root that grows upwards out of the water or mud to reach the air and obtain oxygen for the root systems of trees that live in swampy or tidal habitats. The "knees" of mangroves and the bald cypress are pneumatophores. Also called air root.