collapse vs crack-up

collapse and crack-up both are nouns.

Word	Noun	Adjective	Verb	Adverb
collapse	Yes	No	Yes	No
crack-up	Yes	No	No	No

As nouns, crack-up is a hyponym of collapse; that is, crack-up is a word with a more specific, narrower meaning than collapse:

Other hyponyms of collapse include breakdown, shock, heat hyperpyrexia, heatstroke, algidity.

collapse (noun)	crack-up (noun)
the act of throwing yourself down; collapse; sink	a mental or physical breakdown
a natural event caused by something suddenly falling down or caving in
a sudden large decline of business or the prices of stocks (especially one that causes additional failures)
an abrupt failure of function or complete physical exhaustion

collapse (verb)	crack-up (verb)
collapse due to fatigue, an illness, or a sudden attack
lose significance, effectiveness, or value
suffer a nervous breakdown
break down, literally or metaphorically
fold or close up
fall apart
cause to burst