plunger
名词 plunger:
someone who risks losses for the possibility of considerable gains
同义词:speculator
someone who dives (into water)
同义词:diver
hand tool consisting of a stick with a rubber suction cup at one end; used to clean clogged drains
同义词:plumber's helper
mechanical device that has a plunging or thrusting motion
同义词:piston