plunge

verb

• 1 [no object, with adverbial] jump or dive quickly and energetically:our little daughters whooped as they plunged into the sea
• fall suddenly and uncontrollably:a car swerved to avoid a bus and plunged into a ravine
• (as adjective plunging) denoting a very low-cut neckline on a woman’s garment.
• embark impetuously on a speech or course of action:he came to a decision, and plunged on before he had time to reconsider it
• suffer a rapid decrease in value:shares in the company plunged 18p on news that profits had fallen
• (of a ship) pitch:the ship plunged through the 20-foot seas
• [no object] (of a horse) rear violently: the frightened horse plunged and bolted

• 2 [with object and adverbial] push or thrust quickly:he plunged his hands into his pockets
• quickly immerse in liquid:to peel fruit, cover with boiling water and then plunge them into iced water
• suddenly bring into a specified condition or state:for a moment the scene was illuminated, then it was plunged back into darkness
• [with object] sink (a pot containing a plant) in the ground:pot up and plunge spring-flowering bulbs

noun

• an act of jumping or diving into water:fanatics went straight from the hot room to take a cold plunge
• a swift and drastic fall in value or amount:the central bank declared a 76% plunge in its profits