single-acting: Meaning and Definition of

sin•gle-act•ing

Pronunciation: (sing'gul-ak'ting), [key]
— adj.
  1. (of a reciprocating engine, pump, etc.) having pistons accomplishing work only in one direction. Cf.(def. 1).
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.