From: GUEST,Working Radish

I don't think anyone would call an erhu a Chinese violin - it would sound patronising and fake.

I think that with some there is a kind of snobbery about calling it a fiddle, particularly when it relates to classical music. This probably accounts for the "Chinese Fiddle" rather than "Chinese Violin" - it seems it might be a way of dismissing the instrument for use in "serious" (i.e. Western Classical) music. Possibly a hangover from less enlightened times?