(Bot.) A plant deriving its sustenance from the air alone; an aërophyte. [ 1913 Webster ]

☞ The “Florida moss” (Tillandsia, many tropical orchids, and most mosses and lichens are air plants. Those which are lodged upon trees, but not parasitic on them, such as the Spanish moss Tillandsia usneoides), are epiphytes. [ 1913 Webster ]