borrowed from Caribbean Spanish, earlier, “partying, noisy revelry” of uncertain origin
Note:
Fernando Ortiz Fernández, Glosario de afronegrismos (La Habana, 1924), p. 153, sees bachata as a derivative of bacha, supposedly a synonym, and both as apheretic forms of cumbancha or cumbacha (the latter very rare if it exists), which has approximately the same meaning as bachata. The base of cumbancha, per Ortiz Fernández, is cumbé, “a dance of the blacks, and the music to which they dance” (“un baile de los negros, y el son á que se baila”), as the word is glossed in successive editions of the dictionary of the Real Academia Española, going back to the Diccionario de autoridades (the C volume in 1729), which cites the word in verse by the dramatist Francisco de Castro (1672-1713). These connections are possible, but speculative; the African etymologies proffered by Ortiz Fernández are even more speculative.
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