rash

Probably from Old French rasche, rache (“skin eruption, rash; (specifically) scabies, scurf”) (obsolete), from racher (“to scrape; to scratch”) (although this is only directly attested later than the noun), from Vulgar Latin *rāsicāre (“to scrape”), from Latin rāsus (“scraped, scratched; shaved”), the perfect passive participle of rādō (“to scrape, scratch; to shave; to rub, smooth; to brush along, graze”). Doublet of rase and raze.

Uncertain; the word is similar to other words from Germanic or Romance languages listed in the table below, but the connection between the English word and those words is unclear. One suggestion is that they ultimately derive from the town of Arras in France, known for its cloth and wool industries (whence arras (“tapestry, wall hanging”)); compare German Rasch (“lightly woven silk or (usually) worsted fabric”) (said to be from Middle High German arrasch (“arras”), and ultimately from the name of the town), and the obsolete names for the fabric, Catalan drap de arraz, drap d'Arraç, Spanish paño de ras (literally “cloth of Arras”). The Oxford English Dictionary states that even if rash did not originally derive from Arras, the name of the town could have influenced the English word.

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