Free Electron Laser (FEL)
Free Electron Laser (FEL) : A type of laser which generates radiation by the interaction of an electron beam with a static magnetic or electric field. Loosely speaking, free-electron laser technology resembles and evolved from that used by particle accelerators ("atom smashers"). Lasers which are not free electron lasers are bound electron lasers. Free Rocket A rocket not subject to guidance or control in flight