Glossary

The world of ophthalmology, like many areas of professional medicine, can be difficult to navigate if you don’t know the terms. Use our online glossary to look up and/or familiarize yourself with the various terms you may encounter.

Aberration
A failure of light rays entering the eye to converge on one focus due to irregularities in the cornea and/or crystalline lenses. Common lower order aberrations are conditions such as myopia (near-sightedness), hyperopia (far-sightedness), and astigmatism. More complex higher order aberrations are less common and occur in a much greater variety of ways.

Accommodation
The process by which the eye adjusts focus when you change from looking at an object far away to looking at something close up.

Astigmatism
A very common condition that causes blurred vision, usually due to an irregular shape of the cornea which prevents light entering the eye from being focused properly on the retina.