combustion vs tumultuousness

combustion and tumultuousness both are nouns.

Word	Noun	Adjective	Verb	Adverb
combustion	Yes	No	No	No
tumultuousness	Yes	No	No	No

As nouns, tumultuousness is a hypernym of combustion; that is, tumultuousness is a word with a broader meaning than combustion:

Other hypernyms of combustion include garboil, tumult, uproar.

combustion (noun)	tumultuousness (noun)
the act of burning something	a state of commotion and noise and confusion
a process in which a substance reacts with oxygen to give heat and light
a state of violent disturbance and excitement