in pharmacy, a topical remedy for a disorder of the eyes; designed to cool and repel hot sharp humours.

They are generally of two kinds; the one liquid, and the other dry. Liquid collyria are composed of ophthalmic powders in waters; as rose-water, plantain-water, or that of fennel, eye-bright, &c., wherein tatty, white vitriol, or some other proper powder, is dissolved.

The dry collyrium is troches of rhafis, sugar-candy, tatty prepared, &c., blown into the eye.