mildness vs balminess

mildness and balminess both are nouns.

Word	Noun	Adjective	Verb	Adverb
mildness	Yes	No	No	No
balminess	Yes	No	No	No

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

Other hyponyms of mildness include softness.

mildness (noun)	balminess (noun)
mercifulness as a consequence of being lenient or tolerant	the quality of weather that is deliciously mild and soothing
acting in a manner that is gentle and mild and even-tempered
good weather with comfortable temperatures