closeness vs smallness

closeness and smallness both are nouns.

Word	Noun	Adjective	Verb	Adverb
closeness	Yes	No	No	No
smallness	Yes	No	No	No

As nouns, smallness is a hyponym of closeness; that is, smallness is a word with a more specific, narrower meaning than closeness:

Other hyponyms of closeness include littleness, pettiness, miserliness.

closeness (noun)	smallness (noun)
the spatial property resulting from a relatively small distance	the property of having a relatively small size
characterized by a lack of openness (especially about one's actions or purposes)	lack of generosity in trifling matters
the quality of being close and poorly ventilated	the property of being a relatively small amount
close or warm friendship	the property of having relatively little strength or vigor
extreme stinginess	The quality of being minor in influence, power, or rank.
a feeling of being intimate and belonging together