Someone you are suppose to sleep with to avoid getting your ass beat. This person must get around a lot.
Boy: I cheated on my girlfriend and I think she found out. What should I do?
Friend: You better sleep with One Eye Open.
Boy: Good advice!
Friend: You better sleep with One Eye Open.
Boy: Good advice!
by Dd_NY November 11, 2009
'Sleep with one eye open' is usually used as a metaphor in a sentence. It basically means being very cautious, careful or attentive.
The peddler was sleeping with one eye open. He was shocked, as he heard footsteps approaching him. He looked quite frightened.
by Kittenwool August 21, 2016
Preface: This can't just be me. Ok, Def. When You have drank enough that it is inexplicably comfortable to watch TV or read with just one eye open. To open both eyes actually reduces the quality of visual perception. This stage occurs before any feeling of sickness, but well past the point of which "good judgement" is a consideration.
by Wordsmithin June 20, 2017
by VroomVroomVroomVroomVroom October 06, 2021