noun
one building; the same building
Used as a counter-like noun for a single building or to refer to the same building. Often appears in contexts like real estate, addresses, or describing shared occupancy.
この土地には一棟だけ家が建っている。
There is only one house standing on this land.
彼らは一棟のアパートに住んでいる。
They live in the same apartment building.