To engage in communication and other shared activities (with someone).
To affect each other.
A pair or series of acts involving more than one person.
To associate intimately with; to be close to.
To be similar to, to be almost the same as.
To be adjacent to
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.
One who is near in sympathy or confidence.
A fellow human being.