vt to baptize by immersion.
2. plunge ·noun heavy and reckless betting in horse racing; hazardous speculation.
3. plunge ·vi to pitch or throw one's self headlong or violently forward, as a horse does.
4. plunge ·noun hence, a desperate hazard or act; a state of being submerged or overwhelmed with difficulties.
5. plunge ·noun the act of pitching or throwing one's self headlong or violently forward, like an unruly horse.
6. plunge ·vt to entangle; to embarrass; to overcome.
7. plunge ·noun the act of thrusting into or submerging; a dive, leap, rush, or pitch into, or as into, water; as, to take the water with a plunge.
8. plunge ·vi to bet heavily and with seeming recklessness on a race, or other contest; in an extended sense, to risk large sums in hazardous speculations.
9. plunge ·vi to thrust or cast one's self into water or other fluid; to submerge one's self; to dive, or to rush in; as, he plunged into the river. also used figuratively; as, to plunge into debt.
10. plunge ·vt to thrust into water, or into any substance that is penetrable; to immerse; to cause to penetrate or enter quickly and forcibly; to thrust; as, to plunge the body into water; to plunge a dagger into the breast. also used figuratively; as, to plunge a nation into war.