1) Delusion 2) Psychotic belief 
delusion that one is an animal
• (n.) A kind of monomania in which the patient believes himself transformed into one of the lower animals.
(zo-an´thro-pe) the delusion that one has become an animal. adj., zoanthrop´ic, adj. .
Zo·an'thro·py noun [ Greek ... animal + ... man.] (Medicine) A kind of monomania in which the patient believes himself transformed into one of the lower animals. 
Type: Term Pronunciation: zō-an′thrō-pē Definitions: 1. A delusion that one is an animal, such as a dog.
[n] - the delusion that you have assumed the form of an animal
zoanthropy, zoanthropic A mental derangement in which a person believes himself/herself to be an animal and acts accordingly. —Word Info image © Copyright, 2006.
noun the delusion that you have assumed the form of an animal
a mental disorder in which one believes oneself to be an animal.