Synonyms for Suspicious (same or very similar meaning)
WordNet sense 1 (openly distrustful and unwilling to confide):
leery, mistrustful, wary, untrusting
WordNet sense 2 (having or showing distrust):
distrustful
WordNet sense 3 (not as expected):
fishy, funny, shady, suspect, suspect
WordNet sense 4 (subject to question):
questionable
From the ODE community, based on WordNet
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