1. rotates automatically or by itself without external force
Usage: technical; aviation
2. descends in a helicopter using unpowered rotor blades that spin due to airflow
Usage: aviation; emergency procedure

Examples

• The helicopter autorotates safely to the ground after engine failure.
• The rotor autorotates during the emergency landing procedure.
• When the engine stops, the aircraft autorotates using air flowing upward through the rotor.
• The pilot practiced how the helicopter autorotates in case of power loss.
• The maple seed autorotates as it falls from the tree.
• The turbine autorotates when wind passes through it.