"young ox," Old English steor "bullock," from Proto-Germanic *steuraz (source also of Old Saxon stior, Old Norse stjorr, Swedish tjur, Danish tyr, Middle Dutch, Dutch, German stier, Gothic stiur "bull"), perhaps from PIE *steu-ro-, denoting "larger domestic animal" (see Taurus). In U.S. of male beef cattle of any age.
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<a href="https://www.etymonline.com/word/toro">Etymology of toro by etymonline</a>
Harper, D. (n.d.). Etymology of toro. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/toro