Hallucination n. : The act of hallucinating; a wandering of the mind; error; mistake; a blunder.

Hallucination n. : The perception of objects which have no reality, or of sensations which have no corresponding external cause, arising from disorder or the nervous system, as in delirium tremens; delusion.

Example:
How can I incorporate some awesome Hallucination like imagery into a story?

Taxonomy
hallucinations, perception, hallucinatory, insight, Auditory hallucinations, the brain, voices, smell, sensory perception, Hypnagogic hallucinations, Hypnagogic hallucination, focal epilepsy, free encyclopedia, conscious, delirium tremens, Types of hallucinations, migraine, Phantosmia.

Defination from the web:
hallucination is known as a disturbance, and can occur in any of the senses above. ... Other types of auditory hallucination include exploding head syndrome and musical ear syndrome. ...