leanness vs deficiency

leanness and deficiency both are nouns.

Word	Noun	Adjective	Verb	Adverb
leanness	Yes	No	No	No
deficiency	Yes	No	No	No

As nouns, deficiency is a hypernym of leanness; that is, deficiency is a word with a broader meaning than leanness:

Other hypernyms of leanness include inadequacy, insufficiency.

leanness (noun)	deficiency (noun)
the property of having little body fat	lack of an adequate quantity or number
the quality of being meager	the state of needing something that is absent or unavailable