hallucination hal·lu·ci·na·tion (hə-lōō'sə-nā'shən)
False or distorted perception of objects or events with a compelling sense of their reality, usually resulting from a mental disorder or drug.
The objects or events so perceived.
A false perception that appears to be real, as when, for example, a man dying of thirst in a desert thinks that he sees a lake. (See also delusion.)