keep one's eyes open

Idioms  

1. Also,. Be watchful and observant. For example, We should keep our eyes open for a change in the wind's direction, or Keep your eyes peeled for the teacher. The first phrase dates from the late 1800s; the second and third, both colloquial and alluding to the lids not covering the eyes, date from the mid-1800s and 1830s, respectively.

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Example Sentences

See Examples For:

keep one's eyes open

One had to keep one’s eyes open there, for they were every bit as brave as we were.

From Out on the Pampas Or, The Young Settlers by G. A. (George Alfred) Henty

Thou knowest well how to furnish a guard-room when one is required to keep one's eyes open and one's spirits up.

From King Eric and the Outlaws, Vol. 1 or, the Throne, the Church, and the People in the Thirteenth Century. Vol. I. by Bernhard Severin Ingemann

One cannot keep one's eyes open very long without winking, but the stranger did.

From The Ape, the Idiot & Other People by W. C. Morrow

It is best to be serious and cautious, and to keep one’s eyes open, when one travels that way.

From Ainslee's, Vol. 15, No. 6, July 1905 by Various

It is as well to keep one's eyes open, constable, when investigating a case like this.'

From The Triumphs of Eugène Valmont by Robert Barr