In dated|lang=en terms the difference between upstair and downstair
is that upstair is (dated) upstairs while downstair is (dated) downstairs.
As adjectives the difference between upstair and downstair
is that upstair is (dated) upstairs while downstair is (dated) downstairs.
upstair
English
Adjective
(
-)
(dated) upstairs
- an upstair drawing-room
downstair
English
Adjective
(
-)
(dated) downstairs
- a downstair bedroom