shifty

1. (of a person's eyes) Moving from one object to another; not looking directly and steadily at the person with whom one is speaking.Examples: "1886, George Manville Fenn, This Man’s Wife, Chapter 3, in Littel’s Living Age, Volume 168, No. 2178, 20 March, 1886, p. 761, […] his quick, shifty eyes turned from the manager to the lethal weapons over the chimney, then to the safe, then to the bank, and Mr. Thickens’s back."; "His tinted glasses were not really opaque, but of a blue kind common enough, nor were the eyes behind them shifty, but regarded me steadily."; "He was thin, unsure of himself, sweet-natured and shifty-eyed; and he was Lata’s favourite."

2. (informal, idiomatic) Having the appearance of being dishonest, criminal, or unreliable.Examples: "He was a shifty character in a seedy bar, and I checked my wallet was still there after talking to him."; "‘I don’t trust him,’ he goes on. ‘He is shifty. He is like a jackal sniffing around, looking for mischief. […]’"idiomaticinformal