Optometry \Op*tom"e*try\, n.

1. (Med.) Measurement of the range of vision, esp. by means of the optometer.

2. As defined (with minor variations) in the statutes of various States of the United States:
   (a) ``The employment of subjective and objective mechanical means to determine the accomodative and refractive states of the eye and the scope of its function in general.''
   (b) ``The employment of any means, other than the use of drugs, for the measurement of the powers of vision and adaptation of lenses for the aid thereof.''

Source: Webster's Revised Unabridged Dictionary (1913)