exhaustion vs tiredness

exhaustion and tiredness both are nouns.

Word	Noun	Adjective	Verb	Adverb
exhaustion	Yes	No	No	No
tiredness	Yes	No	No	No

As nouns, tiredness is a hypernym of exhaustion; that is, tiredness is a word with a broader meaning than exhaustion:

exhaustion: extreme fatigue
tiredness: temporary loss of strength and energy resulting from hard physical or mental work

Other hypernyms of exhaustion include fatigue, weariness.

exhaustion (noun)	tiredness (noun)
the act of exhausting something entirely	temporary loss of strength and energy resulting from hard physical or mental work
serious weakening and loss of energy
extreme fatigue