Translation guide
The English word 'adjacent' is used to describe things that are next to or very near each other, often sharing a boundary. In Japanese, there is no single perfect equivalent; the best choice depends on whether you are talking about physical proximity, abstract relationships, or formal/technical contexts.
Describing rooms, buildings, land, or objects that are directly beside each other, often touching or sharing a wall/edge.
The most direct and common translation for 'adjacent' in physical contexts. Used for buildings, rooms, land, etc. that are next to each other. Often used in formal or written descriptions.
I could hear sounds from the adjacent room.
This land is adjacent to the park.
The most natural, everyday word for 'next' or 'adjacent' when referring to rooms, houses, seats, etc. It implies immediate proximity and is used in casual and spoken Japanese.
Is the adjacent room available?
Means 'touching' or 'adjoining'. Used when two things are in direct contact, like two pieces of land or objects. Slightly more technical than 隣接した.
The two countries are adjacent along the border.
Emphasizes immediate adjacency, like 'right next door'. Very common in speech.
The house immediately adjacent caught fire.
Describing things that are close by, in the vicinity, or neighboring without sharing a boundary.
The most common way to say 'nearby' or 'adjacent' in a loose sense. Used for locations, buildings, etc. that are close but not necessarily touching.
Describing concepts, fields, or topics that are closely related or next to each other in a non-physical sense.
Can be used metaphorically for fields of study, topics, etc. that are closely related or 'adjacent'. Often used in academic or technical contexts.
Specifically referring to adjacent angles, sides, or vertices in mathematics or technical drawings.
The standard term in geometry for 'adjacent', as in adjacent angles or sides.
隣の席に座ってもいいですか？
May I sit in the adjacent seat?
The hotel is adjacent to the station. (nearby)
More formal than 近くの, often used in written notices or announcements to mean 'in the vicinity' or 'adjacent area'.
An evacuation advisory was issued for residents in adjacent areas.
This research is in a field adjacent to psychology.
A simple and common way to say 'close' or 'adjacent' in an abstract sense, like ideas or concepts that are similar or related.
Those two concepts are very adjacent (closely related).
The sum of two adjacent angles is 180 degrees.
the building next door (casual)
While 隣接した is a correct translation, it can sound stiff in everyday conversation. Use 隣の or 近くの unless you need a formal or technical tone.