Repulsorlift
In the Star Wars universe, a Repulsorlift engine ("repulsor") is a device capable of negating the effects of gravity. As such, it can be used to levitate items or assist spacecraft during take-off and landing.
Usage
Repulsorlifts exist in a variety of sizes, from shipboard systems capable of supporting mile-long spacecraft[1] to the miniature versions built into certain droids[2]. They require a gravity well to operate, limiting their use to the immediate vicinity of planets or other sources of gravity[3]. Unlike chemical thrusters, repulsorlifts do not seem to adversely affect whatever is located underneath them[4]. Their silent operation and low power requirements makes them suited for use in densely populated areas. Their popularity and widespread indicate an excellent degree of reliability.
Repulsorlifts have difficulty operating when exposed to certain electromagnetic phenomena or when they pass through shields.