Source : Webster's Revised Unabridged Dictionary (1913)

Pas \Pas\, n. [F. See {Pace}.]
   1. A pace; a step, as in a dance. --Chaucer.

   2. Right of going foremost; precedence. --Arbuthnot.

Source : WordNet®

pas
     n : (ballet) a step in dancing (especially in classical ballet)