rash

UK: /ˈræʃ/ US: /ræʃ/ ,(rash)

Inflections of 'rash' (adj):

rasher

adj comparative

rashest

adj superlative

WordReference Random House Learner's Dictionary of American English © 2026

rash¹ /ræʃ/   adj., -er, -est. 

1. acting quickly and without thinking:
   a rash leader.
2. made or done quickly or without careful thought:
   rash promises.

rash•ly, adv. 
rash•ness, n. [uncountable]

rash² /ræʃ/   n. [countable]

1. Pathology an area of spots or redness on the skin resulting from an irritation or disorder of some kind.
2. numerous occurrences of something at about the same time:
   a rash of robberies.

WordReference Random House Unabridged Dictionary of American English © 2026

rash¹  (rash), adj. -er, -est. 

1. acting or tending to act too hastily or without due consideration.
2. characterized by or showing too great haste or lack of consideration:
   rash promises.

• 1350–1400; Middle English; cognate with Dutch, German rasch quick, brisk, Old Norse rǫskr brave

rash′ly, adv. 
rash′ness, n. 
Synonyms

• 1. hasty, impetuous, reckless, venturous, incautious, precipitate, indiscreet, foolhardy.

Antonyms

• 1. cautious.

rash²  (rash), n. 

1. Pathology an eruption or efflorescence on the skin.
2. a multitude of instances of something occurring more or less during the same period of time:
   a rash of robberies last month.

• Latin rādere to scratch
• French rache (obsolete), Old French rasche skin eruption, derivative of raschier to scratch, ultimately
• 1700–10

rash′like′, adj. 

Collins Concise English Dictionary © HarperCollins Publishers::

rash / ræʃ/ adjective

1. acting without due consideration or thought; impetuous
2. characterized by or resulting from excessive haste or impetuosity: a rash word

Etymology: 14th Century: from Old High German rasc hurried, clever; related to Old Norse roskr brave

ˈrashly adverb

ˈrashness noun

rash / ræʃ/ noun

1. any skin eruption
2. a series of unpleasant and unexpected occurrences: a rash of forest fires

Etymology: 18th Century: from Old French rasche, from raschier to scratch, from Latin rādere to scrape