n an abrupt failure of function or complete physical exhaustion
n a natural event caused by something suddenly falling down or caving in
n the act of throwing yourself down
n a sudden large decline of business or the prices of stocks (especially one that causes additional failures)
v break down, literally or metaphorically
v collapse due to fatigue, an illness, or a sudden attack
v fold or close up
v fall apart
v cause to burst
v suffer a nervous breakdown
v lose significance, effectiveness, or value
