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borracho m. (Adjective, Noun) "drunk;" "drunkard"
15th cent. Linguists are divided into two camps regarding this word's etymology. Following Corominas (1991) and RAE, the word is from borracha. Following Corriente (1999) and Roberts (2014), the word is from either Latin burrus or Mozarabic murrus, both meaning "reddish," and Roberts adds "so called in allusion to the complexion of an intoxicated person." In his survey of both theories, Dworkin (2012) writes that "most specialists agree that borracho 'drunk; drunkard' derives secondarily from substantival borracha.