n. The use of light to treat disorders of the skin, and certain mood disorders.
the GNU version of the Collaborative International Dictionary of English
n. The application of light for therapeutic purposes, esp. for treating diseases of the skin.
The Century Dictionary and Cyclopedia
n. Treatment of disease by rays derived from the sun or an electric lamp; Finsen treatment; light treatment. It is really a form of radiotherapy, for the rays employed are the non-luminous ultra-violet rays and not those of light.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. the use of strong light to treat acne or hyperbilirubinemia of the newborn
Word Usage
"And phototherapy, which is those ultraviolet purple lights, can break down the bilirubin until the baby's liver can catch up."