closeness vs contiguity

closeness and contiguity both are nouns.

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

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

Other hyponyms of closeness include propinquity, proximity, adjacency, contiguousness, localness.

closeness (noun)	contiguity (noun)
the spatial property resulting from a relatively small distance	the attribute of being so near as to be touching
characterized by a lack of openness (especially about one's actions or purposes)
the quality of being close and poorly ventilated
close or warm friendship
extreme stinginess
a feeling of being intimate and belonging together