neighborliness vs neighbourliness

neighborliness and neighbourliness both are nouns.

Word	Noun	Adjective	Verb	Adverb
neighborliness	Yes	No	No	No
neighbourliness	Yes	No	No	No

As nouns, neighborliness and neighbourliness are synonyms defined as:

neighborliness and neighbourliness: a disposition to be friendly and helpful to neighbors

Other synonyms of neighborliness include good-neighborliness, good-neighbourliness.

neighborliness (noun)	neighbourliness (noun)
a disposition to be friendly and helpful to neighbors	a disposition to be friendly and helpful to neighbors