easiness vs tranquility

easiness and tranquility both are nouns.

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

As nouns, tranquility is a hypernym of easiness; that is, tranquility is a word with a broader meaning than easiness:

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

Other hypernyms of easiness include quietness, quietude, tranquillity.

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