impugn (v.)

• abjure
• accuse
• anathematize
• anathemize
• arraign
• assail
• attack
• belie
• blame
• censure
• condemn
• contest
• contradict
• contravene
• controvert
• counter
• criminate
• cross
• damn
• decry
• denounce
• deny
• disallow
• disavow
• disclaim
• disown
• disprove
• dispute
• forswear
• gainsay
• impeach
• implicate
• incriminate
• inculpate
• indict
• involve
• negate
• negative
• nullify
• oppose
• recant
• refute
• renounce
• reprehend
• reproach
• reprobate
• repudiate
• retract
• revoke
• traverse