heartsease vs peace of mind

heartsease and peace of mind both are nouns.

Word	Noun	Adjective	Verb	Adverb
heartsease	Yes	No	No	No
peace of mind	Yes	No	No	No

As nouns, heartsease and peace of mind are synonyms defined as:

Other synonyms of heartsease include ataraxis, peace, peacefulness, repose, serenity.

heartsease (noun)	peace of mind (noun)
the absence of mental stress or anxiety	the absence of mental stress or anxiety
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