noun
master bedroom; main bedroom
Refers to the largest bedroom in a house, typically used by the head of the household or the primary occupants. Common in real estate and home design contexts.
このマンションの主寝室はとても広いです。
The master bedroom in this apartment is very spacious.
主寝室にはウォークインクローゼットが付いています。
The master bedroom comes with a walk-in closet.