adjacency vs contiguousness

adjacency and contiguousness both are nouns.

Word	Noun	Adjective	Verb	Adverb
adjacency	Yes	No	No	No
contiguousness	Yes	No	No	No

As nouns, adjacency and contiguousness are synonyms defined as:

adjacency and contiguousness: the attribute of being so near as to be touching

Other synonyms of adjacency include contiguity.

adjacency (noun)	contiguousness (noun)
the attribute of being so near as to be touching	the attribute of being so near as to be touching