As an adjective nextdoor
is an alternative spelling of next-door.
As an adverb nextdoor
is an alternative spelling of next-door.
As a noun neighbor is
standard spelling of from=American spelling|lang=en.
As a verb neighbor is
standard spelling of from=American spelling|lang=en.
nextdoor
English
Adjective
(-)
(nonstandard)
Adverb
(-)
(nonstandard)