jejuneness vs inadequacy

jejuneness and inadequacy both are nouns.

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

As nouns, inadequacy is a hypernym of jejuneness; that is, inadequacy is a word with a broader meaning than jejuneness:

Other hypernyms of jejuneness include inadequateness.

jejuneness (noun)	inadequacy (noun)
the quality of being vapid and unsophisticated	unsatisfactoriness by virtue of being inadequate
quality of inadequate nutritive value	lack of an adequate quantity or number
lacking and evidencing lack of experience of life	a lack of competence