The Collaborative International Dictionary of English v.0.48:

Myopia \My*o"pi*a\, n. [NL. See Myope.] (Med.)
   Nearsightedness; shortsightedness; a condition of the eye in
   which the rays from distant object are brought to a focus
   before they reach the retina, and hence form an indistinct
   image; while the rays from very near objects are normally
   converged so as to produce a distinct image. It is corrected
   by the use of a concave lens.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

ametropia \am`e*tro"pi*a\ ([a^]m`[-e]*tr[=o]"p[i^]*[.a]), n.
   [Gr. 'a`metros irregular + 'w`ps, 'wpo`s, eye.] (Med.)
   A visual impairment resulting from faulty refraction of light
   rays in the eye. Subtypes include myopia astigmatism and
   hyperopia. -- Am`e*trop"ic ([a^]m`[-e]*tr[o^]p"[i^]k), a.
   AS
   [1913 Webster +PJC]

WordNet (r) 3.0 (2006):

myopia
    n 1: (ophthalmology) eyesight abnormality resulting from the
         eye's faulty refractive ability; distant objects appear
         blurred [syn: myopia, nearsightedness,
         shortsightedness] [ant: farsightedness,
         hypermetropia, hypermetropy, hyperopia,
         longsightedness]