second floor; upstairs
Refers to the second story of a building or the upstairs area. In Japanese floor counting, the ground floor is 一階, so 二階 is one floor above ground level.
My room is on the second floor.
I heard a loud noise from upstairs.
I went up the stairs to the second floor.
The child came down from the second floor.
We live on the second floor.
full two-story house
second floor front room
twelve level cap and rank system