Living in a high-rise building: how to describe that you share the same entrance with another person?

Question

Suppose you live in a condo (a 24-story residential tower block). There are many entrances to the building. Let's say, six.

People who enter the same entryway and cross the same entrance space (or hallway? - it's where the mailboxes are) use the same elevator to access their apartments on different floors.

Now a friend of yours lives three floors below you.

Is it possible to say he or she is your "downstairs neighbor"?

How can one underline this relative proximity, the state of "living next to each other in the vertical dimension"?

To me, a next-door neighbor would be someone living on the same floor (a horizontal proximity).

But what if I need to speak of someone living above me or below me? Not necessarily one floor up or down. Could be several.

I specifically mean those who share the same elevator with me. People who are fellow residents of the same condo, but who use a different entrance to the building, must remain outside my scope (because we never see each other and never cross paths).

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Thanks for considering this scenario.

Answer 1

Regardless of the fact they do not live on the same floor as you, they are still your 'neighbour', or US 'neighbor'.

Oxford English Dictionary defines neighbour as:

A person living next door to or very near to the speaker or person referred to. ‘our garden was the envy of the neighbours’

1.1 A person or place in relation to others next to or near to it.

https://en.oxforddictionaries.com/definition/neighbour

Therefore, you can use 'your downstairs neighbor' as you asked.