43 synonyms for suspicious such as dark, apprehensive, corrupt, and criminal. Suspicious is an adjective, and its antonyms are trustful and trusting.
Apprehensive, chary, cynical, disbelieving, distrustful, doubtful, dubious, having reservations, iffy, jaundiced, mistrustful, sceptical, unsure, and wary.
Corrupt, criminal, dark, dishonest, dishonest-looking, disreputable, dodgy, doubtful, dubious, fishy, funny, funny-looking, guilty-looking, irregular, murky, mysterious, not quite right, odd, queer, questionable, shady, shifty, slippery, strange, strange-looking, suspect, under suspicion, and unsavoury.