|Origin:||plongier, from Vulgar Latin plumbicare, from Latin plumbum 'lead'|
1 [intransitive,transitive always + adverb/preposition]
to move, fall, or be thrown suddenly forwards or downwards
if a price, rate etc plunges, it suddenly decreases by a large amount:
The unemployment rate plunged sharply.
In the recession, the company's profits plunged 60%.
3 [intransitive] literary
if a ship plunges, it moves violently up and down because of big waves
plunge inphrasal verb
to start talking or doing something quickly and confidently, especially without thinking about it first:
It's a difficult situation. You can't just plunge in and put everything right.
'I don't agree,' she said, plunging into the conversation.
to jump or dive into water:
He stripped off and plunged into the sea.
plunge (somebody/something) into somethingphrasal verb
A strike would plunge the country into chaos.
The house was suddenly plunged into darkness.
After the war, the family plunged into debt.