Optometry (Greek: optos meaning seen or visible and metria meaning measurement) is a health care profession concerned with eyes and related structures, vision, visual system and vision information processing in humans
{i} practice of examining the eyes to diagnose visual defects and prescribe corrective lenses or other forms of treatment
"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
As defined (with minor variations) in the statutes of various States of the United States: "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
Profession concerned with examining the eyes for defects or faults of refraction. Optometrists prescribe optical aids (e.g., eyeglasses, contact lenses), supervise eye exercise programs to treat vision problems, and examine the eyes for disorders such as glaucoma and cataracts. They are generally not licensed to prescribe drugs or trained to perform surgery. See also ophthalmology