  The effects of the stellar rotation and the consequent azimuthal stellar wind
flow in Parker's [9] hydrodynamic stellar wind model are discussed. Of special
interest is the emergence of a whole new hydrodynamic physics via a new
critical point in the stellar wind flow, which supersedes the critical point in
Parker's [9] hydrodynamic model. The effect of the stellar rotation is shown to
cause the new critical point to occur lower in the corona, so the stellar wind
experiences a stronger afterburner (as in an aircraft jet engine) action in the
corona. For strong rotators, the new critical point is shown to occur at a
fixed location for a given star, determined only by the basic stellar
parameters like the mass M and the angular velocity, the variations in the
stellar wind environment notwithstanding. The stellar rotation leads to
stronger density fall-off and enhanced acceleration of the stellar wind at
large distances from the star - this effect materializes even close to the
star, for strong rotators. The stellar rotation causes the physical throat
section of the effective de Laval nozzle associated with the stellar wind flow
to become narrower, indicative of an enhanced flow acceleration. Thus, the
stellar rotation leads to tenuous and faster stellar wind flows without change
in the mass flux, and hence provides an efficient physical mechanism for
protostars and strong rotators to lose their angular momentum quickly.
