Definitions:
an act or movement of putting one leg in front of the other in walking or running

a flat surface, especially one in a series, on which to place one's foot when moving from one level to another

a measure or action, especially one of a series taken in order to deal with or achieve a particular thing

an interval in a scale; a tone (whole step) or semitone (half step).

an abrupt change in the value of a quantity, especially voltage.

a block fixed to a boat's keel in order to take the base of a mast or other fitting.

lift and set down one's foot or one foot after the other in order to walk somewhere or move to a new position

set up (a mast) in its step.