Mid 19th century; earliest use found in John William Donaldson (1811–1861), philologist. From ancient Greek μονόϕθαλμος one-eyed (from μονο- + ὀϕθαλμός eye: see ophthalmo-) + -ic. Compare post-classical Latin monoptalmus, monophthalmus, adjective and noun (from 670 in British sources), French monophthalme, adjective and noun.