There's any number of names for them - there's quite a few different cultures who use them too - in South East Asia and the Pacific Islands they're used as courting/mating instruments.

The name jews harp is probably the most common in English and is generally accepted by the leading 'harpists around the country.

There is no evidence that it has anything to do with Judaism but no one has a definative reason for the name. Anyone who tell you otherwise can probably give you an exact definition of the term "folk music" as well.

pax yall