tranquility vs easiness

tranquility and easiness both are nouns.

Word	Noun	Adjective	Verb	Adverb
tranquility	Yes	No	No	No
easiness	Yes	No	No	No

As nouns, easiness is a hyponym of tranquility; that is, easiness is a word with a more specific, narrower meaning than tranquility:

tranquility: a state of peace and quiet
easiness: a feeling of refreshing tranquility and an absence of tension or worry

Other hyponyms of tranquility include ataraxis, heartsease, peace, peace of mind, peacefulness, repose, serenity, relaxation.

tranquility (noun)	easiness (noun)
a disposition free from stress or emotion	the quality of being easy in behavior or style
a state of peace and quiet	freedom from difficulty or hardship or effort
an untroubled state; free from disturbances	a feeling of refreshing tranquility and an absence of tension or worry