radical

a.激进的；彻底的；(数学)根的；基本的

racket (also racquet), racket-press, racketeer, racketeering, rackety, raconteur, racoon, racy, RADA, radar, radar trap (also speed trap), radial, radially, radiance, radiant, radiantly, radiate, radiation, radiation sickness, radiator, radicalism, radically, radicle, radii, radio, radio astronomer, radio astronomy, radio car, radio cab, radio frequency, radio telescope, radio transmitter, radio-, radio-astronomer, radio-carbon, radio-controlled, radio-frequency, radio-therapist, radio-therapy, radioactive, radioactivity,