Definition
A rotorcraft that gets its lift from a freely spinning rotor turned by the airflow passing through it as the aircraft moves forward. Forward thrust is provided by a separate engine-driven propeller, not by the rotor itself. The rotor is unpowered in flight and spins through a process called autorotation.
Plain English
A small aircraft with an overhead rotor that spins on its own as the aircraft is pushed forward by a propeller. The spinning rotor creates the lift, but the engine never drives the rotor in flight.
Context Anchor
Seen in discussions of gyroplanes, light sport aircraft, experimental aircraft, and rotorcraft operating limitations.
Derivation
From Greek 'gyros' (circle, ring) and 'copter' (shortened from helicopter, itself from Greek 'helix' spiral and 'pteron' wing). The 'gyro' part points to the freely turning rotor that defines the aircraft.
Why Pilots Care
A gyrocopter looks like a helicopter at a glance but flies very differently. It cannot hover, and the rotor is not engine-driven. Mistaking one for the other leads to serious misunderstandings about handling, performance, and emergency procedures.
Intuition Check
Do not assume “gyrocopter” means “helicopter.” In a gyrocopter, the top rotor normally spins because air flows through it, while a separate propeller moves the aircraft forward.
Example Sentence 1
The gyrocopter lifted off after a short ground roll once the rotor was spinning fast enough to produce lift.
Example Sentence 2
Gyrocopters can land in very short distances because the rotor continues turning even after the engine is idled.