nigh vs adjacent

nigh and adjacent both are adjectives.

Word	Noun	Adjective	Verb	Adverb
nigh	No	Yes	No	Yes
adjacent	No	Yes	No	No

nigh (adjective)	adjacent (adjective)
not far distant in time or space or degree or circumstances	nearest in space or position; immediately adjoining without intervening space
being on the left side	having a common boundary or edge; abutting; touching
	near or close to but not necessarily touching

nigh (adverb)	adjacent (adverb)
near in time or place or relationship
(of actions or states) slightly short of or not quite accomplished; all but