Distichiasis is a condition in which extra eyelashes grow on the eyelid line in areas where they should not grow. (vesnebraska.com)
The symptoms or clinical signs will vary with the severity of the condition, including the number of extra eyelashes, their size and their stiffness. (glenerinanimalhospital.com)
It differs from entropian in that it is a condition in which extra eyelashes (termed distichiae) grow out from the inner margin of the eyelid whereas entropion results from an inward roll of the eyelid that causes eye irritation from normal eyelashes. (thebedlingtonterrierhealthgroup.webplus.net)