emmetropia n 1: (ophthalmology) the normal refractive condition of the eye in which there is clear focus of light on the retina
Emmetropia \Em`me*tro"pi*a\ ([e^]m"m[-e]*tr[=o]"p[i^]*[.a]), n. [NL., fr. Gr. 'e`mmetros in measure, proportioned, suitable ('en in + me`tron measure) + 'w`ps, 'wpo`s, eye.] (Med.) That refractive condition of the eye in which the rays of light are all brought accurately and without undue effort to a focus upon the retina; -- opposed to {hypermetropia}, {myopia}, and {astigmatism}. [1913 Webster]