to expel (an evil spirit) by solemn command, e.g. in a religious ceremony
to free (a person or place) of an evil spirit
to get rid of (an unpleasant thought or emotion) as if by exorcism
exorcism /-siz(ə)m/ noun
exorcist noun
exorcizer noun
[Middle English exorcisen via French and late Latin from Greek exorkizein, from ex out + horkizein to bind by oath, adjure, from horkos oath]