suspicious
Concise Oxford English Dictionary © 2008 Oxford University Press:
suspicious/səˈspɪʃəs/
▶adjective having or showing cautious distrust.
■ causing one to believe that someone or something is questionable, dishonest, or dangerous.
■ believing that someone is involved in illegal or dishonest activity.
– derivatives
suspiciously adverb,
suspiciousness noun.
suspiciously adverb,
suspiciousness noun.
'suspicious' also found in these Oxford entries:

