Demonize is defined as to make someone come across as a demon or to portray someone as bad or evil.(verb)
When you tell everyone that your new teacher is as mean and evil as the Devil himself, this is an example of a time when you demonize the teacher.
See demonize in Webster's New World College Dictionary
See demonize in American Heritage Dictionary 4
transitive verb de·mon·ized, de·mon·iz·ing, de·mon·iz·es
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