Stair
Part of speech: noun
Definition: A single step in a staircase. A series of steps, a staircase.
Step
Part of speech: verb
Definition: To move the foot in walking; to advance or recede by raising and moving one of the feet to another resting place, or by moving both feet in succession.To walk; to go on foot; esp., to walk a little distance.To walk slowly, gravely, or resolutely.To move mentally; to go in imagination.To set, as the foot.To fix the foot of (a mast) in its step; to erect.
Part of speech: noun
Definition: An advance or movement made from one foot to the other; a pace.A rest, or one of a set of rests, for the foot in ascending or descending, as a stair, or a rung of a ladder.A running board where passengers step to get on and off the bus.The space passed over by one movement of the foot in walking or running. Used also figuratively of any kind of progress.A small space or distance.A print of the foot; a footstep; a footprint; track.A gait; manner of walking.Proceeding; measure; action; act.() A walk; passage.(plural): A portable framework of stairs, much used indoors in reaching to a high position.A framing in wood or iron which is intended to receive an upright shaft; specif., a block of wood, or a solid platform upon the keelson, supporting the heel of the mast.One of a series of offsets, or parts, resembling the steps of stairs, as one of the series of parts of a cone pulley on which the belt runsA bearing in which the lower extremity of a spindle or a vertical shaft revolves.The interval between two contiguous degrees of the scale.A change of position effected by a motion of translation. - William Kingdon Clifford
Example sentence: The first step in solving a problem is to recognize that it does exist.