lightsomeness vs insouciance

lightsomeness and insouciance both are nouns.

Word	Noun	Adjective	Verb	Adverb
lightsomeness	Yes	No	No	No
insouciance	Yes	No	No	No

As nouns, lightsomeness and insouciance are synonyms defined as:

lightsomeness and insouciance: the cheerful feeling you have when nothing is troubling you

Other synonyms of lightsomeness include carefreeness, lightheartedness.

lightsomeness (noun)	insouciance (noun)
the trait of being lighthearted and frivolous	the cheerful feeling you have when nothing is troubling you
the gracefulness of a person or animal that is quick and nimble
the cheerful feeling you have when nothing is troubling you