Definition of greys
(especially of hair) become gray with age.
Dapper, charming, and handsome, with a full head of sandy hair that greyed attractively over the years, Felt resembled actor Lloyd Bridges.
a gray thing or animal, in particular a gray or white horse.
Eager equestrians were paraded round the ring by charming chestnuts and graceful greys in the popular horse classes.
gray color or pigment.
I know that grey isn't the best background colour to use on a webpage, but I'll put up with it.
the SI unit of the absorbed dose of ionizing radiation, corresponding to one joule per kilogram.
Radiation doses are measured in rads or grays , where 1 gray equals 100 rads.