EYESALVE (Gr. kollourion). A preparation compounded of various ingredients used either by simple application or by reduction to a powder to be smeared on the eye (Rev.3.18). When used figuratively it refers to the restoration of spiritual vision.

EYESALVE (κολλούριον, G3141; variant in many MSS, κολλύριον). The word appears in the context of the address to the church at Laodicea (Rev 3:18). The term is a diminutive of the Gr. kollura, “little cake,” a very common dosage form in the Hel. world. It has been suspected that this particular prescription for the spiritual blindness at Laodicea had some special reference to a product of that place, but such assumptions lack sufficient evidence to be more than speculations.

International Standard Bible Encyclopedia (1915)

(kollourion; collyrium; Re 3:18):

A Phrygian powder mentioned by Galen, for which the medical school of Laodicea seems to have been famous (see Ramsay, The Letters to the [[Seven Churches]] of Asia), but the figurative reference is to the restoring of spiritual vision.