Read the dictionary definition of unimpeachable. All definitions for this word.
1. completely acceptable; not open to exception or reproach
1. two unexceptionable witnesses
2. a judge's ethics should be unexceptionable
2. free of guilt; not subject to blame
1. has lived a blameless life
2. of irreproachable character
3. an unimpeachable reputation
3. beyond doubt or reproach
1. an unimpeachable source