Definition

1. Verb (intransitive):

   • To collapse inward or downward, especially suddenly. This can refer to a physical structure literally falling into an empty space below or within it.
   • To yield or submit under pressure, either physically or metaphorically (e.g., in an argument or negotiation).

2. Noun:

   • The event or instance of a sudden collapse into a hollow space.

Usage and Examples

• Verb (Literal Collapse):

  • The old mine roof could cave in at any moment.
  • Heavy rains caused the ground to cave in above the buried tunnel.

• Verb (Metaphorical Yield/Surrender):

  • After hours of negotiation, they finally caved in and accepted our terms.
  • Don't cave in to peer pressure; stand by your decision.

• Noun:

  • The cave-in trapped several miners underground. (Note: Often hyphenated as a noun.)
  • Engineers investigated the cause of the cave-in.

Advanced Usage and Nuances

• The phrasal verb often implies a failure to withstand pressure, leading to a sudden change from a state of resistance to one of collapse or submission.
• In metaphorical use, it frequently describes a person or group abandoning a position, argument, or resolve.

Variants and Related Words

• Cave-in (n): The nominalized, often hyphenated form.
• Collapse (v/n): A close synonym for both the physical and metaphorical senses.
• Give way (v): A synonym, especially for the physical sense of collapsing.
• Buckled (adj): Describes something that has bent or collapsed under pressure.

Synonyms

• Verb: Collapse, give way, buckle, fall in, submit, yield, capitulate, give in.
• Noun: Collapse, subsidence, implosion.

Related Phrasal Verbs

• Give in: To yield or surrender. Very similar in metaphorical use to "cave in."
  • She refused to give in to their demands.
• Break down: To cease to function; to collapse emotionally or structurally.
  • The talks broke down over key issues.

Idioms and Common Phrases

• To cave in under the strain: To finally collapse or yield because the pressure or stress became too great.
  • The administration caved in under the strain of public protest.
• A cave-in of morale: A metaphorical expression describing a sudden loss of spirit or confidence within a group.
  • The team's losing streak led to a complete cave-in of morale.

Noun

1. the sudden collapse of something into a hollow beneath it

Verb

1. break down, literally or metaphorically
   • The wall collapsed
   • The business collapsed
   • The dam broke
   • The roof collapsed
   • The wall gave in
   • The roof finally gave under the weight of the ice