n.手压皮碗泵；撞针杆；活塞；柱跳水者，潜水者 变形： 复数：plungers 英英释义： plunger[ 'plʌndʒə ]n.someone who risks losses for the possibility of considerable gains同义词：speculatorsomeone who dives (into water)同义词：diverhand tool consisting of a stick with a rubber suction cup at one end;