[keyv-in] 
| 1. | a collapse, as of anything hollow: the worst cave-in in the history of mining. |
| 2. | a place or site of such a collapse. |
| 3. | submission to something or someone previously opposed or resisted: His cave-in to such unreasonable demands shocked us. |
[keyv] noun, verb, caved, cav⋅ing.| 1. | a hollow in the earth, esp. one opening more or less horizontally into a hill, mountain, etc. |
| 2. | a storage cellar, esp. for wine. |
| 3. | English History. a secession, or a group of seceders, from a political party on some special question. |
| 4. | to hollow out. |
| 5. | Mining.
|
| 6. | to cave in. |
| 7. | cave in,
|
cave in
Fall in, collapse, as in The earthquake made the walls cave in. [Early 1700s]
Give in, admit defeat, as in The prosecutor's questions soon made the witness cave in. [Early 1800s]
Collapse, faint, or die from exhaustion, as in After a twenty-mile hike I caved in. [Mid-1800s]