Helicopter

n. highly maneuverable aircraft which flies by means of horizontally rotating blades

A helicopter is an aircraft which is lifted and propelled by one or more horizontal rotors, each rotor consisting of two or more rotor blades. Helicopters are classified as rotorcraft or rotary-wing aircraft to distinguish them from fixed-wing aircraft because the helicopter derives its source of lift from the rotor blades rotating around a mast. The word 'helicopter' is adapted from the French hélicoptère, coined by Gustave de Ponton d'Amecourt in 1861.
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Noun
1. an aircraft without wings that obtains its lift from the rotation of overhead blades
(synonym) chopper, whirlybird, eggbeater
(hypernym) heavier-than-air craft
(hyponym) cargo helicopter
(part-meronym) blade, vane

A heavier than air aircraft supported in flight chiefly by the reactions of the air on one or more power driven rotors on substantially vertical axes. (FAA4)

A rotary-wing aircraft which depends principally for its support and motion in the air upon the lift generated by one or more power-driven rotors, rotating on substantially vertical axes. A helicopter is a V/STOL. (AIA1)

A rotorcraft that, for its horizontal motion, depends principally on its engine-driven rotors. (14CFR1)

See also Gyroplane.

[ICAO]
A heavier-than-air aircraft supported in flight chiefly by the reactions of the air on one or more power-driven rotors on substantially vertical axes.
 

Rotorcraft that, for its horizontal motion, depends principally on its engine-driven rotors.
(See ICAO term HELICOPTER.)