(step) noun
1. An act of progressive motion that requires one of the supporting limbs of the body to be thrust in the direction of the movement, and to reassume its function of support; a pace.
2. The distance passed over in making such a motion; in military quick–time marching, 30 inches.
3. Any short distance; a space easily traversed.
4. That upon which the foot rests in ascending or descending, as a stair or ladder rung.
5. A single action or proceeding regarded as leading to something: a step toward emancipation.
6. An advance or promotion that forms one of a series, especially in military usage; grade; degree.
7. The manner of stepping; walk; gait; also, the sound of a footfall.
8. A footprint; track.
9. plural Progression by walking; walk.
10. A combination of foot movements in dancing, forming a pattern that may be repeated, varied, or elaborated: the tango step.
11. An interval measuring a difference of musical pitch, corresponding to a degree of the scale or staff.
12. A socket, supporting framework, pocket, or the like: the step of a mast.
13. A steplike projection or part, as of the bit of a key.
14. Mech. The radial distance between the face of one pulley and that of another stepped on the same shaft.
15. A break in the contour of a float or hull, as of a seaplane, designed to lessen resistance and improve control.
16. A stage in cascade amplification.
—in step In agreement or synchronism when marching, dancing, etc.; walking evenly with another by taking corresponding steps.
—out of step Not in step.
—to take steps To adopt measures, as to attain an end.
—v. stepped, step·ping v.i.
1. To move forward or backward by taking a step or steps.
2. To go by foot; walk a short distance: to step across the street.
3. To move with measured, dignified, or graceful steps.
4. To move or act quickly or briskly: The old man was stepping down the road.
5. To pass into a situation, circumstance, etc., as if in a single step: He stepped into a fortune.
—v.t.
6. To take (a pace, stride, etc.).
7. To perform the steps of: to step a quadrille.
8. To place or move (the foot) in taking a step.
9. To measure by taking steps: often with off: to step off five yards.
10. To cut or arrange in steps.
11. Naut. To place the lower end of (a mast) in its step.
—to step down
1. To decrease gradually, or by steps or degrees.
2. To resign from an office or position; abdicate.
—to step in To begin to take part; intervene.
—to step on (or upon)
1. To put the foot down on; tread upon.
2. To put the foot on so as to activate, as a brake or treadle.
3. Colloq. To reprove or subdue.
—to step on it To hurry; hasten.
—to step out
1. To go outside, especially for a short while.
2. Colloq. To go out for fun or entertainment.
3. To step down (def. 2).
4. To walk vigorously and with long strides.
—to step up To increase; raise. ♦ Homophone: steppe. [OE stœpe]

Related through the previous marriage of a parent or spouse, but not by blood: stepchild. [OE steop- <stem of astypan, astepan bereave, orphan]