A person living on adjacent or nearby land; a person situated adjacently or nearby; anything (of the same type of thing as the subject) in an adjacent or nearby position.
My neighbour has two noisy cats.
One who is near in sympathy or confidence.
A fellow human being.
To be adjacent to
Though France neighbours Germany, its culture is significantly different.
(followed by "on"; figurative) To be similar to, to be almost the same as.
That sort of talk is neighbouring on treason.
To associate intimately with; to be close to.