quietness vs heartsease

quietness and heartsease both are nouns.

Word	Noun	Adjective	Verb	Adverb
quietness	Yes	No	No	No
heartsease	Yes	No	No	No

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

Other hyponyms of quietness include ataraxis, peace, peace of mind, peacefulness, repose, serenity, easiness, relaxation.

quietness (noun)	heartsease (noun)
the property of making no sound	the absence of mental stress or anxiety
a state of peace and quiet	common Old World viola with creamy often violet-tinged flowers
	violet of Pacific coast of North America having white petals tinged with yellow and deep violet
	a common and long cultivated European herb from which most common garden pansies are derived