A portico; a covered walk.
A covered entrance to a building, whether taken from the interior, and forming a sort of vestibule within the main wall, or projecting without and with a separate roof. A porch often has chair(s), table(s) and swings.
The platform outside the external hatch of a spacecraft.
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.