next-door
UK: /ˌnɛkst ˈdɔː/ | US: /ˌnɛkst ˈdɔːr/
adj. located or living in the adjacent building or room
adj. very close or nearby in relationship or context
The term "next-door" combines "next" (from Old English neahst, meaning "nearest" or "adjacent") and "door" (from Old English duru, meaning "entryway"). Historically, it literally referred to the immediate neighboring house or room separated by a door or wall. Over time, it evolved metaphorically to describe anything closely connected or proximate in context.
My next-door neighbor is always friendly and helpful.
She moved into the next-door apartment last month.
The next-door café serves the best coffee in town.
Their next-door rivalry has lasted for years.
The noise from the next-door party kept me awake all night.