A plant that grows on another plant or object above the ground, and which has no roots in the soil. An epiphyte does not parasitize the plant it grows on. but merely uses it for support. It's nutrients are obtained from rainwater, organic debris such as leaf litter, or from the air. The greatest diversity of epiphytes is found in tropical areas and includes many orchids.
An example of an Epiphyte is the Epicactus 'Space Rocket', which is pictured right.
In addition you may interested in the website of
The Journal of the Epiphytic Plant Study Group 'Epiphytes'.