A system of gears that has a central gear wheel (sun gear) around which others (planet gears) rotate, often within an outer ring.

(mechanics) A wheel with a toothed rim, intended to engage with others, or similar equipment, to form a gear.

The highest gear that is available in a motor vehicle or car.

(uncountable, countable, aviation) The wheels, tyres, brakes, shock absorbers etc of an aircraft; its undercarriage.

(mechanical engineering) A system of interconnected gears.

Alternative spelling of gearstick

Synonym of interrupter gear

A triggering device attached to the machine gun armament of fighter aircraft so that the gun could fire through the arc of a spinning propeller without the bullets striking the blades.

plural of bottom gear

The lowest gearing available from a gearbox, typically in a motor vehicle or cycle.