crumple vs break down

crumple and break down both are verbs.

Word	Noun	Adjective	Verb	Adverb
crumple	No	No	Yes	No
break down	No	No	Yes	No

As verbs, crumple and break down are synonyms defined as:

Other synonyms of crumple include collapse, crumble, tumble.

crumple (verb)	break down (verb)
become wrinkled or crumpled or creased	collapse due to fatigue, an illness, or a sudden attack
to gather something into small wrinkles or folds	stop operating or functioning
fold or collapse	separate (substances) into constituent elements or parts
fall apart	make a mathematical, chemical, or grammatical analysis of; break down into components or essential features
	make ineffective
	cause to fall or collapse
	lose control of one's emotions
	fall apart