quadcopter - Computer Definition
(QUAD heliCOPTER) A helicopter with two pairs of rotors (vertically oriented propellers). One pair rotates clockwise; the other counter clockwise, and the flight path is controlled by the speed of each rotor. Manned quadcopters date back to the 1920s; however, consumer models appeared for aerial photography and just plain fun after the turn of the century. See personal drone and insect drone.