transitive verb plunged, plunging plung′·ing

Etymology: ME plungen < OFr plongier < VL *plumbicare < L plumbum, lead: see plumb

intransitive verb

1. to throw oneself, dive, or rush, as into water, a fight, etc.
2. to move violently and rapidly downward or forward
3. to pitch, as a ship
4. to slope steeply, as a road
5. to extend far down in a revealing way a plunging neckline or back
6. Informal to spend, gamble, or speculate heavily or rashly

noun

1. 1. a dive or downward leap
   2. a swim
2. any sudden, violent plunging motion
3. a place for plunging, or swimming
4. Informal a heavy, rash investment or speculation