to cast or thrust forcibly or suddenly into something, as a liquid, a penetrable substance, a place, etc.; immerse; submerge

to plunge a dagger into one's heart.

to bring suddenly or forcibly into some condition, situation, etc.

to plunge a country into war; to pull a switch and plunge a house into darkness.

Horticulture . to place (a potted plant) up to its rim in soil or in certain other materials, as sand or moss.

Surveying . to transit (the telescope of a transit or theodolite).

to cast oneself, or fall as if cast, into water, a hole, etc.

to rush or dash with headlong haste

to plunge through a crowd.

to bet or speculate recklessly

to plunge on the stock market.

to throw oneself impetuously or abruptly into some condition, situation, matter, etc.

to plunge into debt.

to descend abruptly or precipitously, as a cliff, road, etc.

to pitch violently forward, as a horse, ship, etc.

act of plunging.

a leap or dive, as into water.

a headlong or impetuous rush or dash

a plunge into danger.

a sudden, violent pitching movement.

a place for plunging or diving, as a swimming pool.

Geology . pitch ( def. 48 ) . ?

take the plunge, to enter with sudden decision upon an unfamiliar course of action

as after hesitation or deliberation

She took the plunge and invested her entire savings in the plan.

noun

ascent , increase , rise

verb

ascend , increase , rise

noun

belly flop , descent , dive , duck , dunk , fall , high dive , immersion , investment , jump , nose-dive , spree , submergence , submersion , swoop , venture , nosedive , pitch , spill , tumble , decline , dip , downslide , downswing , downtrend , downturn , drop , drop-off , skid , slide , slump , swim

verb

belly-flop , career , cast , charge , dash , descend , dip , drive , drop , duck , fling , go down , go the limit , go whole hog , hurtle , immerge , immerse , jump , keel , lunge , lurch , nose-dive , pitch , plummet , plunk , propel , rush , shoot the works , sink , sound , submerge , submerse , swoop , take a flyer , take a header , tear , throw , throw oneself , thrust , topple , tumble , dive , wade in , dig , run , stab , stick , spill , forge , skid , slump , absorb , douse , dump , engulf , fall , souse , swim