1. (

• hallucination

) illusory perception; a common symptom of severe mental disorder ;

2. (

• delusion ,
• hallucination

) a mistaken or unfounded opinion or idea; "he has delusions of competence"; "his dreams of vast wealth are a hallucination" ;

3. (

• hallucination ,

) an object perceived during a hallucinatory episode; "he refused to believe that the angel was a hallucination" ;