The word 'sunburned' is a transparent Modern English compound, directly combining two native Germanic elements. 'Sun' originates from the Proto-Germanic sunnōn, a feminine noun whose Proto-Indo-European root sóh₂wl̥ also gives us Latin sol and Greek hēlios. 'Burned' derives from the Old English verb bærnan, related to the Proto-Germanic brinnaną (to burn), from the PIE root bʰrenw- (to bubble, burn). The compound's logic is perfectly literal: it describes the condition of skin that has been 'burned by the sun,' where the sun's radiation is metaphorically equated with fire in its damaging effect. This straightforward descriptive formation replaced the more classical term 'heliosis' in common usage.

Structure: sun (the star) + burned (damaged by fire/heat) - sun: From Old English sunne, of Germanic origin; related to Dutch zon and German Sonne. The noun referring to the celestial body. - burned: The past participle of the verb burn, from Old English birnan (to be on fire) and bærnan (to set on fire), of Germanic origin. In this compound, it functions as an adjective-forming element meaning "affected by burning."