on the floor; above floor level
Refers to something being placed or happening on the floor surface, or at a height above the floor. Often used in contexts like cleaning, storage, or construction.
床上に荷物を置かないでください。
Please do not place luggage on the floor.
床
I installed a shelf 30 centimeters above the floor.
inundation above floor level; flooding above floorboards
Compound of 床 (yuka, 'floor') and 上 (ue, 'above/on'). The reading is a straightforward combination of the two components.