threefold; triple.-acute; sharp; as, a treble sound.-playing or singing the highest part or most acute sounds; playing or singing the treble; as, a treble violin or voice.-trebly; triply.-the highest of the four principal parts in music; the part usually sung by boys or women; soprano.-to make thrice as much; to make threefold.-to utter in a treble key; to whine.-to become threefold.