Lewis & Short

in-sōlo, āvi, ātum, 1, v. a. [in-sol], to place in the sun, i. e. expose to the sun, in order to warm, dry, etc. (a favorite word with Columella): uvas, Col. 12, 39, 2: insolati dies, sunny, sunshiny days, id. 11, 3, 51: humus insolatur, becomes warmed, id. 4, 17, 8.