From Longman Dictionary of Contemporary Englishnext doorˌnext ˈdoor1 ●●● S2 adverb 1 NEXT TOin the house, room etc next to yours or someone else’s the boy next door Her office is just next door.2 → next door to something
Examples from the Corpus
next door• Deanna's office is right next door.• The boy next door cuts our grass for us.next doornext door2 noun [uncountable] British English informal NEXT TOthe people living in the house or apartment next to yours SYN neighbour Have you seen next door’s new car?next-doorˈnext-door adjective [only before noun] 1 → next-door neighbour2 → next-door apartment/office etcExamples from the Corpus
next-door• It would be ironic to pick away at the mortar for a few decades only to break through into the next-door cell.• And when was the last time you stayed at a motel and got to know your next-door neighbors?• He could be the next-door neighbour, a friend, a blood relation.• I haven't had any trouble with him personally, but my next-door neighbour has.• Could some one tell my next-door neighbour, Mrs Timms?• Better than a view of cardboard panes and the next-door privies. 