#1 plunge v. [immerse] thrust or throw into; "Immerse yourself in hot water". wn
#2 plunge v. [dive, plunk] drop steeply; "the stock market plunged". wn
#3 plunge v. dash violently or with great speed or impetuosity; "She plunged at it eagerly". wn
#4 plunge v. [launch] begin with vigor; "He launched into a long diatribe"; "She plunged into a dangerous adventure". wn
#5 plunge n. [dip] a brief swim in water. wn
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