neighbouring vs neighboring

neighbouring and neighboring both are adjectives.

Word	Noun	Adjective	Verb	Adverb
neighbouring	No	Yes	No	No
neighboring	No	Yes	No	No

As adjectives, neighbouring and neighboring are synonyms defined as:

neighbouring and neighboring: having a common boundary or edge; abutting; touching

Other synonyms of neighbouring include adjacent, conterminous, contiguous.

neighbouring (adjective)	neighboring (adjective)
having a common boundary or edge; abutting; touching	having a common boundary or edge; abutting; touching