Photo of a cat with sleep in their eyes with the caption Rheum from a cat's eyes Rheum from the eyes is particularly common. Dried rheum near the eyes is commonly called 'sleep', 'sleet', 'sleepy-seeds', 'sleepy buds', 'sleepy bugs', 'sleepy sand', 'sleepy winks', 'eye boogers', 'eye goop', 'sleepy dust', 'sleepies', 'eye gunk, ‘eye crust', 'sleepy men', 'crusties', 'dozy dust', 'eye globs', or 'sleepy dirt'.
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