Subbasement [noun]

● Vault

● Apartment

● Basement

● Subterrane

● Underground room

● Attic

● Subbasement

● Basement

● Storeroom

● Upstairs

● Broom closet

● Cellar

● Crawlspace

● Attic

● Stairwell

● Cavelike

● Root cellar

● Downstairs

● Dumbwaiter

● Elevator

● Catacomb

● Rabbit warren

● Garage

● Undercroft

● Alcove

● Hatchway

● Elevator shaft

● Antechamber

● Underground

● Closet

● Hallway

● Strongroom

● Cockloft

● Workroom

● Cavern

● Coatroom

● Staircase

● Crypt

● Scullery

● Spiral staircase

● Loft

● Cubbyholes

● Freight elevator

● Floors

● Firetrap

● Vaults

● Skylit

● Musty

● Rathskeller

● Washhouse

● Dank

● Brownstone

● Building

● Cubicles

● Anterooms

● Bowels

● Rumpus room

● Garret

● Quonset hut

● Tomblike

● Dungeon

● Bathysphere

● Warren

● Diningroom

● Vestibules

● Gaslights

● Annexe

● Kneehole

● Newel post

● Recesses

● Ceilings

● Hoistway

● Doorless

● Beaux arts

● Mansard

● Mildewing

● Carrel

● Quonset

● Passageway

● Rowhouse

● Genizah

● Speakeasy

● Breezeways

● Airlocks

● Potting shed

● Cinder block

● Storage room

● Hovel

● Atrium

● Lair

● Edifice

● Wine cellar

● Corncrib

● Cupola

● Belowground

● Postholes

● Rooms

● Semidarkness

● Bowfront

● Rolltop

● Rotunda

● Flophouse

● Breezeway

● Sanctum

● Ballroom

● Washateria