Pace1  —n. 1 a single step in walking or running. B distance covered in this. 2 speed in walking or running. 3 rate of movement or progression. 4 way of walking or running; gait (ambling pace). —v. (-cing) 1 a walk slowly and evenly (pace up and down). B (of a horse) amble. 2 traverse by pacing. 3  set the pace for (a rider, runner, etc.). 4 (foll. By out) measure by pacing.  keep pace (often foll. By with) advance at an equal rate (to). Put a person etc. Through his (or her) paces test a person's qualities in action etc. Set the pace determine the speed; lead. [french pas from latin passus]