coolness vs chilliness

coolness and chilliness both are nouns.

Word	Noun	Adjective	Verb	Adverb
coolness	Yes	No	No	No
chilliness	Yes	No	No	No

As nouns, coolness and chilliness are synonyms defined as:

Other synonyms of coolness include nip.

As nouns, coolness and chilliness are synonyms defined as:

Other synonyms of coolness include coldness, frigidity, frigidness, iciness.

coolness (noun)	chilliness (noun)
the property of being moderately cold	the property of being moderately cold
a lack of affection or enthusiasm	a lack of affection or enthusiasm
fearless self-possession in the face of danger
calm and unruffled self-assurance