Synonyms for Criminal (same or very similar meaning)
WordNet sense 1 (someone who has committed (or been legally convicted of) a crime):
crook, felon, malefactor, outlaw
WordNet sense 2 (bringing or deserving severe rebuke or censure):
deplorable, reprehensible, vicious, condemnable
WordNet sense 3 (contrary to conscience or morality or law):
wrong
WordNet sense 4 (involving or being or having the nature of a crime):
felonious
WordNet sense 5 (prohibited by law or by official or accepted rules):
illegal
WordNet sense 6 (responsible for or chargeable with a reprehensible act; or marked by guilt):
guilty
From the ODE community, based on WordNet
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