Discredit
noun
Discrediting or disbelieving.
A person or thing that causes harm to a reputation, as of a person, family, or institution.
The state of being discredited or disbelieved.
“Later accounts have brought the story into discredit.”
Synonyms: demerit
verb
To harm the good reputation of a person; to cause an idea or piece of evidence to seem false or unreliable.
“The candidate tried to discredit his opponent.”
Synonyms: demean, disgrace, dishonour, disprove, invalidate, tell against