solidifying vs natural action

solidifying and natural action both are nouns.

Word	Noun	Adjective	Verb	Adverb
solidifying	Yes	No	No	No
natural action	Yes	No	No	No

As nouns, natural action is a hypernym of solidifying; that is, natural action is a word with a broader meaning than solidifying:

solidifying: the process of becoming hard or solid by cooling or drying or crystallization
natural action: a process existing in or produced by nature (rather than by the intent of human beings)

Other hypernyms of solidifying include action, activity, natural process.

solidifying (noun)	natural action (noun)
the process of becoming hard or solid by cooling or drying or crystallization	a process existing in or produced by nature (rather than by the intent of human beings)