The adjective is derived from Middle English rash, rasch (“hasty, headstrong, rash”) [and other forms], probably from Old English *ræsċ (“rash”) (found in derivatives such as ræsċan (“to move rapidly; to flicker; to flash; to glitter; to quiver”), ræsċettan (“to crackle, sparkle”), etc.), from Proto-West Germanic *rask, *raskī, *rasku, from Proto-Germanic *raskaz, *raskuz, *raþskaz, *raþskuz (“rash; rapid”), from Proto-Indo-European *Hreth₂- (“to run, roll”). The Middle English word was probably influenced by the cognates listed below. The adverb is derived from Middle English rashe (“quickly, rapidly”), from rash, rasch (adjective) (see above). Cognates * Dutch ras, rasch (“rash”) * Middle Low German rasch (“rash”) * Old Danish rask (“agile, nimble; fast; healthy, vigorous”) (modern Danish rask (“agile, nimble; fast; healthy, vigorous; hasty, rash”)) * Old High German reski (“impetuous, rash”) (Middle High German rasch, resch (“agile, nimble; fast; lively; healthy, vigorous”), modern German rasch, räsch, resch (“agile, nimble; fast; hasty, rash; healthy, vigorous; of food: crisp, crusty”)) * Old Norse rǫskr (“brave; healthy, vigorous”) (Icelandic röskur (“strong; healthy, vigorous”)) * Old Swedish rasker (“agile, nimble; brave; fast; vigorous”) (modern Swedish rask (“agile, nimble; fast; healthy, vigorous”))

rashly • adventurous • Blizzard • cockbrained • daring • devil-may-care • dire • efflorescence • epidemic • foolhardy • headstrong • heady • heedless • hotheaded • impetuous • imprudent • impulsive • inconsiderate • instant • lavish • precipitant • precipitate • precipitous • precipitously • quick-and-dirty • reckless • roseola • sudden • temeritous • unthinking