break down vs decease

break down is not a noun while decease is a noun.

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

break down (noun)	decease (noun)
	the event of dying or departure from life

break down (verb)	decease (verb)
collapse due to fatigue, an illness, or a sudden attack	pass from physical life and lose all bodily attributes and functions necessary to sustain life
stop operating or functioning
separate (substances) into constituent elements or parts
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