Arroyo

wiktionary

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From Spanish arroyo.

etymonline

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arroyo (n.)

"watercourse, dry stream bed," 1845, a California word, from American Spanish, in Spanish, "rivulet, small stream," perhaps from Latin arrugia "shaft or pit in a gold mine," which is apparently a compound of ad "to" (see ad-) + ruga "a wrinkle" (see rugae).