eye out

[eye out] Careful watch or attention; guard. - Used after "keep","have" or "with".

Keep an eye out. We're close to Joe's house.

-Usually used with "for".

Mary has her eye out for bargains.

They went through the woods very quietly, with an eye out forIndians.

Compare: LOOK OUT(2), ON GUARD, ON THE ALERT, ON THE WATCH.