What is the meaning of plunge?

noun

• A brief swim in water.
  • synonyms: dip
• A steep and rapid fall.

verb

• Thrust or throw into.
  • usage: "Immerse yourself in hot water"
  • synonyms: immerse
• Drop steeply.
  • usage: "the stock market plunged"
  • synonyms: dive, plunk
• Dash violently or with great speed or impetuosity.
  • usage: "She plunged at it eagerly"
• Begin with vigor.
  • usage: "He launched into a long diatribe"; "She plunged into a dangerous adventure"
  • synonyms: launch
• Cause to be immersed.
  • usage: "The professor plunged his students into the study of the Italian text"
  • synonyms: immerse
• Fall abruptly.
  • usage: "It plunged to the bottom of the well"
  • synonyms: dump
• Immerse briefly into a liquid so as to wet, coat, or saturate.
  • usage: "dip the garment into the cleaning solution"; "dip the brush into the paint"
  • synonyms: dunk, dip, souse, douse
• Devote (oneself) fully to.
  • usage: "He immersed himself into his studies"
  • synonyms: steep, immerse, engulf, engross, absorb, soak up