A porch, or a small space with a roof supported by columns, serving as the entrance to a building.
A connected set of flights of stairs; a stairwell.
A flight of stairs; a stairway.
A set of locks (enclosed sections of waterway) mounted one above the next.
To modify (a signal, a graph, etc.) to reduce a smooth curve to a series of discrete steps.
To increase one's share in a co-ownership.