verb (used with object)
to injure the credit
or reputation of; defame: an effort to discredit honest politicians.
to show to be undeserving of trust or belief; destroy confidence in: Later research discredited earlier theories.
to give no credence to; disbelieve: There was good reason to discredit the witness.
loss or lack of belief or confidence; disbelief; distrust: His theories met with general discredit.
loss or lack of repute or esteem; disrepute.
something that damages a good reputation: This behavior will be a discredit to your good name.
1. disparage, disgrace, tarnish, undermine.