Sunburn

wiktionary

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From Middle English *sunne burnen, *sonne brennen, *sunne brennen (suggested by derivatives sonne brennynge, sunne brennynge(“sunburn”, literally “sun-burning”) and sunne brente(“sunburnt”), equivalent to sun +‎ burn. Compare West Frisian sinnebrân(“sunburn”), Dutch zonnebrand(“sunburn”), German Sonnenbrand(“sunburn”), Swedish solbränna(“sunburn”), Icelandic sólbruni(“sunburn”).

etymonline

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sunburn (v.)

1520s, from sun (n.) + burn (v.). Sunburnt (c. 1400) is older than sunburned (c. 1500, sunne y-brent). As a noun from 1650s.