What physical condition does the Kármán line approximate regarding aerodynamic flight?

Answer

The altitude where the atmosphere becomes too thin to support practical aerodynamic flight.

The Kármán line signifies the approximate altitude where the atmosphere is too thin for a craft to rely on wings for lift, necessitating orbital velocity to stay aloft.

What physical condition does the Kármán line approximate regarding aerodynamic flight?
SpaceorbitISSKármán line