Somehow the word zebu came up, and I thought “That’s an odd word, I wonder where it came from?” Turns out nobody knows; the OED says (in an unrevised entry) “< French zébu (Buffon, who states that it was shown under this name at a fair in Paris in 1752).” I thought surely more must be known by now, but no, the latest Merriam-Webster Collegiate and the latest American Heritage Dictionary both just say it’s from zébu. There are more details at Hobson-Jobson, which takes a sensible attitude:
This whimsical name, applied in zoological books, English as well as French, to the humped domestic ox (or Brahminy bull) of India, was taken by Buffon from the exhibitors of such a beast at a French fair, who perhaps invented the word, but who told him the beast had been brought from Africa, where it was called by that name. We have been able to discover no justification for this in African dialects, though our friend Mr. R. Cust has kindly made search, and sought information from other philologists on our account. Zebu passes, however, with most people as an Indian word; thus Webster’s Dictionary, says “Zebu, the native Indian name.” The only word at all like it that we can discover is zobo (q.v.) or zhobo, applied in the semi-Tibetan regions of the Himālaya to a useful hybrid, called in Ladak by the slightly modified form dsomo. In Jäschke’s Tibetan Dict. we find “Ze’-ba . . . . l. hump of a camel, zebu, etc.” This is curious, but, we should think, only one of those coincidences which we have had so often to notice.