But just because the word "juju" is listed in a Yoruba dictionary does not mean it comes from that language said Azizi.

I'd always understood (though I haven't got a citation by me) that "juju" came from the French "jou-jou", a childish word for a toy, and referred to the doll- like figures used in some religious contexts. Quite a lot of words considered to be of exotic origin are actually boomeranged European words, such as joss-house (a temple) from "Dios".

I recently had the pleasure of showing a local Asian shopkeeper that his name, Mistry, was in fact European, and comes from the same root as "maestro".

There's an excellent dictionary of Imperial-English words, "Hobson-Jobson", which is available in the UK on the budget Wordsworth imprint, and lists many such examples.