Preception of object without external stimulus called ?

Hallucination -False perception which occurs in the absence of any real object / stimulus. Hallucination are as vivid as a real preception . vivid - > detailed /clarity Superstition - a false belief which is unexplained by reality and is shared by a number of people. Delusions - disorder of content of thoughts which is firm ,false , unshakable(despite continuous evidence against it) and is not explained by socio cultural background of patient.