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plunge

(plŭnj)

v. plunged, plung·ing, plung·es

v.intr.

a. To dive, jump, or throw oneself: We plunged into the lake.

b. To fall rapidly: The car went off the road and plunged into the gully.

2. To devote oneself to or undertake an activity earnestly or wholeheartedly: I plunged into my studies. She plunged ahead with her plan.

3. To enter or move headlong through something: The hunting dogs plunged into the forest.

4. To slope steeply downward: a cliff that plunges to the sea.

5. To move forward and downward violently: The ship plunged through rough seas.

6. To become suddenly lower; decrease dramatically: Stock prices plunged during the banking crisis.

v.tr.

1. To thrust or throw forcefully into a substance or place: plunged the eggs into the hot water; plunged the fork into the potato.

2. To cast suddenly, violently, or deeply into a given state or situation: "The street was plunged in cool shadow" (Richard Wright).

3. To use a plunger to try to unblock (a drain, for example).

1. The act or an instance of plunging: a plunge off the dock.

2. A swim; a dip.

3. A sudden or dramatic decline: a plunge in prices.

Idiom:

take the plunge Informal

To begin an unfamiliar venture, especially after hesitating: After a three-year engagement, they're finally taking the plunge.

[Middle English plungen, from Old French plongier, from Vulgar Latin *plumbicāre, to heave a sounding lead, from Latin plumbum, lead.]

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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