jejuneness vs vapidity

jejuneness and vapidity both are nouns.

Word	Noun	Adjective	Verb	Adverb
jejuneness	Yes	No	No	No
vapidity	Yes	No	No	No

As nouns, jejuneness and vapidity are synonyms defined as:

Other synonyms of jejuneness include jejunity, tameness, vapidness.

jejuneness (noun)	vapidity (noun)
the quality of being vapid and unsophisticated	the quality of being vapid and unsophisticated
quality of inadequate nutritive value
lacking and evidencing lack of experience of life