decrepitate vs decrepitation

decrepitate is not a noun while decrepitation is a noun.

Word	Noun	Adjective	Verb	Adverb
decrepitate	No	No	Yes	No
decrepitation	Yes	No	No	No

decrepitate (noun)	decrepitation (noun)
	the crackling or breaking up of certain crystals when they are heated

decrepitate (verb)	decrepitation (verb)
to roast or calcine so as to cause to crackle or until crackling stops
undergo decrepitation and crackle