  Waveguiding in general and acoustic waveguiding in particular are possible at
the condition of having a transverse "discontinuity" or modulation of the
refractive index. We propose here a radically different approach that relies on
imposing spinning on a column of air, leading to high modified acoustic
refractive indices for specific azimuthal modes. Such discovery may be
leveraged to realize not only the airborne acoustic counterpart of the optical
fiber, i.e., the acoustic spinning fiber (ASF), but also nonreciprocal
unidirectional waveguiding mechanism, reminiscent of the ''acoustic Zeeman
effect''. The concept is demonstrated in the realm of acoustics, yet it can be
applicable to other wave systems, e.g., photonics or elastodynamics.
