Definitionen
1.NounThe state or fact of being turbulent or agitated; tempestuousness, disturbance.
2.NounDisturbance in a gas or fluid, characterized by evidence of internal motion or unrest.
3.NounSpecifically, a state of agitation or disturbance in the air which is disruptive to an aircraft.
4.NounAn instance or type of such state or disturbance.