heliotherapy

[ hee-lee-oh-ther-uh-pee ]
/ ˌhi li oʊˈθɛr ə pi /

noun

treatment of disease by means of sunlight.

Origin of heliotherapy

First recorded in 1885–90; helio- + therapy

British Dictionary definitions for heliotherapy

heliotherapy
/ (ˌhiːlɪəʊˈθɛrəpɪ) /

noun

the therapeutic use of sunlight