downstairs

UK: ˌdaʊnˈsteəz | US: ˌdaʊnˈsterz

Definition
  1. adv. on or to a lower floor of a building

  2. adj. located on a lower floor

  3. n. the lower floor(s) of a building

Structure
down <lower>stairs <steps>
Etymology

The word "downstairs" is a straightforward compound of "down" (Old English dūne, meaning "from a higher to a lower position") and "stairs" (Old English stǣger, meaning "steps"). It emerged in Middle English (14th century) to describe movement or location toward or on a lower floor. The logic is spatial: "down" indicates direction, while "stairs" specifies the means of vertical movement.

Examples
  1. She ran downstairs to answer the door.

  2. The downstairs bathroom is currently being renovated.

  3. He left his keys on the downstairs table.

  4. The noise came from the downstairs neighbors.

  5. Please carry the boxes downstairs carefully.