Great stuff, IB. I once did a long interview with Daniel Hamar of Muszikas, who plays the Gardon as well as cello, bass and other instruments.

I also once interviewed the guys in Lo Jai. Guy Bertrand used to play a big string tabor in that group, essentially like the tambourin de Bearn mentioned by Jack.

My own feeling is that fiddle is a word much older than the violin proper, and with wider meaning than "violin." Because the violin is by far the most common bowed stringed instrument, "fiddle" almost always means "violin" in ordinary usage. But not always--I have mentioned "bass fiddle" as a common American expression for the double bass.

Ethnomusicologists don't have any problem using "fiddle" to mean, generically, "bowed lute," as in this passage from the University of Michigan's Instrument Encyclopedia here:

As part of the generic "lute" family, there are two basic types of rebab: wooden fiddles with pear-shaped or elongated bodies, and spiked fiddles, named for the extension or spike on the bottom of the instrument on which it stands when played. Generally, both styles have 2 or 3 gut or other strings. Spike-fiddle rebabs used in the Javanese gamelan are made from wood, or sometimes from a hollowed, half coconut shell covered with hide. This body is attached to a long, narrow wooden neck which has no frets; instead, the fingers of your left hand become moveable bridges. These instruments ornament the melodic line, creating a dialogue with the singers.