- Not impeachable; not to be called in question;
exempt from liability to accusation; free from stain, guilt, or fault;
irreproachable; blameless; as, an unimpeachable reputation;
unimpeachable testimony.
Meaning of 'unimpeachable' (Princeton's WordNet)
1 . unimpeachable
[ s]
Meaning (1): - completely acceptable; not open to exception or reproach
Example in sentence:
a judge's ethics should be unexceptionable;
two unexceptionable witnesses
Meaning (2): - free of guilt; not subject to blame