The American Heritage® Dictionary of the English Language, 4th Edition
n. An abnormal sensitivity to or intolerance of light, especially by the eyes, as may be caused by eye inflammation, lack of pigmentation in the iris, or various diseases.
n. Symptom of excessive sensitivity to light and the aversion to bright light.
the GNU version of the Collaborative International Dictionary of English
n. A dread or intolerance of light.
The Century Dictionary and Cyclopedia
n. An intolerance or dread of light.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. pain in the eye resulting from exposure to bright light (often associated with albinism)
n. a morbid fear of light
Word Usage
"So you know, when a patient has this sort of symptoms which are sometimes stiff neck, they may have headache, they may have what is known as photophobia, which is aversion to lights."