master bedroom
US /ˈmæs.tɚ ˌbed.ruːm/
UK /ˈmæs.tɚ ˌbed.ruːm/

1.
the main bedroom in a house, usually the largest one and often with an attached bathroom
:
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The house has three bedrooms, including a spacious master bedroom with an en-suite bathroom.
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They decided to redecorate the master bedroom first.