B1
in the next room, house, or building
Dictionary examples:
The next-door school's bell is so loud, I wake up for classes I don't take! (0.0)
My next-door neighbor's Wi-Fi password is 'YoullNeverGuessThis'. Guess what? I did! (0.0)
My next-door neighbor's cat thinks it's a opera singer at 3 AM. (0.0)
What are your next-door neighbors like? (32.1)