- The definition of a countershaft is a middle shaft that brings motion from the main shaft to a working part of a machine.
An example of a countershaft is a part of a factory tool that carries motion from the main shaft to the machine's functional part.
countershaft definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
an intermediate shaft that transmits motion from the main shaft of a machine to a working part
countershaft definition by American Heritage Dictionary
An intermediate shaft between the powered and driven shafts in a belt drive.