Coolant turbine for rotary cutting tool; rotary cutting tool; coolant turbine module; and method for operating a rotary cutting tool

A rotary cutting tool, comprising a chuck having a tool receptacle opening, at least one coolant supply passage, and an axially open groove that is arranged on the front face so as to run annularly around the tool receptacle opening, wherein a turbine base body of a coolant turbine is arranged so as to be freely rotatable in the groove, wherein the coolant turbine includes an annular turbine base body having a first front face, an opposite second front face, and a plurality of coolant passages, which are arranged so as to be distributed around a central axis of the turbine base body, said passages having a coolant inlet and a coolant outlet, each of which extends through the turbine base body at least in portions in such a way that the turbine base body can be set into rotation by a flow of coolant.