2. Hence, a desperate hazard or act; a state of being submerged or overwhelmed with difficulties. [R.] She was brought to that plunge, to conceal her husband's murder or accuse her son. Sir P. Sidney. And with thou not reach out a friendly arm, To raise me from amidst this plunge of sorrows Addison.

3. The act of pitching or throwing one's self headlong or violently forward, like an unruly horse.

4. Heavy and reckless betting in horse racing; hazardous speculation. [Cant] Plunge bath, an immersion by plunging; also, a large bath in which the bather can wholly immerse himself. — Plunge, or plunging, battery (Elec.), a voltaic battery so arranged that the plates can be plunged into, or withdrawn from, the exciting liquid at pleasure.

PLUNGER
Plun"ger, n.

1. One who, or that which, plunges; a diver.

2. A long solid cylinder, used, instead of a piston or bucket, as a forcer in pumps.

3. One who bets heavily and recklessly on a race; a reckless speculator. [Cant]

4. (Pottery)

Defn: A boiler in which clay is beaten by a wheel to a creamy consistence. Knight.

5. (Gun.)