The names of animals that have red eyes.
Types of beverages.
(travel) An overnight airplane flight.
I waited too late to book my holiday flight, so I had to take the red-eye.
Redness of the conjunctiva; especially when caused by conjunctivitis (pink-eye).
Redness in the eye(s) of someone in a colour photograph, as an unwanted consequence of light from a flash reflecting off blood vessels in the retina.