plunger plunger /ˈplʌndʒɝ/

noun

1. Mechanical device that has a plunging or thrusting motion  ( piston , plunger )
   mechanical device that has a plunging or thrusting motion
   
   
2. Hand tool consisting of a stick with a rubber suction cup at one end; used to clean clogged drains  ( plumber's helper [ N. American] , plunger , plumber's friend )
   hand tool consisting of a stick with a rubber suction cup at one end; used to clean clogged drains
    The plunger helped clear the blocked sink
   The plunger helped clear the blocked sink
   
   
3. Someone who dives (into water)  ( diver , plunger )
   someone who dives (into water)
    As a scuba diver, I love exploring the underwater world and seeing all the different species of fish
   As a scuba diver, I love exploring the underwater world and seeing all the different species of fish
   
   
4. Someone who risks losses for the possibility of considerable gains  ( plunger , speculator )
   someone who risks losses for the possibility of considerable gains