(of a person's eyes) Moving from one object to another; not looking directly and steadily at the person with whom one is speaking.
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.
(informal, idiomatic) Having the appearance of being dishonest, criminal, or unreliable.
He was a shifty character in a seedy bar, and I checked my wallet was still there after talking to him.
Resourceful; full of, or ready with, shifts or expedients.