staircase

noun
  1. A set of stairs and its surrounding structure, often including a balustrade, that provides a means of access between different levels of a building. noun
    The grand staircase in the mansion was made of marble and had intricate carvings.
    She ascended the staircase quietly, trying not to wake anyone.
  2. A flight of steps with a handrail, typically indoors, that connects different floors within a building. noun
    The fire escape was a metal staircase attached to the outside of the building.
    He tripped on the staircase and sprained his ankle.