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suspicious-looking; shady; questionable; dubious; fishy
その投資話は胡散臭い。
That investment scheme sounds fishy.
政治家の説明は少し胡散臭かった。
The politician's explanation sounded a little fishy.
店の前に胡散臭く立っている男がいた。
There was a man standing suspiciously in front of the shop.