an instrument for measuring the reflection of an image on the surface of the cornea and other capacities of the eye, used chiefly for determining the presence and degree of astigmatism
[1835–45; ophthalmo- + -meter]This word is first recorded in the period 1835–45. Other words that entered Englishat around the same time include: basic, catch-up, communism, grandstand, placementophthalmo- is a combining form meaning “eye,” used in the formation of compound words. Otherwords that use the affix ophthalmo- include: ophthalmodynamometer, ophthalmologist, ophthalmology, ophthalmoscope, ophthalmoscopy; -meter is a combining form meaning “measure,” used in the names of instruments measuringquantity, extent, degree, etc. Other words that use the affix -meter include: altimeter, chronometer, gravimeter, manometer, micrometer