Dictionary.net

One step of a series for ascending or descending to a different level; -- commonly applied to those within a building.

A series of steps, as for passing from one story of a house to another; -- commonly used in the plural; but originally used in the singular only.

One of a set of steps for ascending or descending.

Series of steps for ascending; one of such steps.

One of a series of steps.

A series of steps; usually plural.

A step; a series of steps to ascend by. Flight of stairs, a stair from one landing to another.

n. [Anglo-Saxon] One step of a series for ascending or descending to a different level ;-a series of steps, as for passing from one story of a house to another-commonly in the plural.