Countershaft is a synonym of jackshaft.
As nouns the difference between jackshaft and countershaft
is that jackshaft is a common mechanical component used to transfer or synchronize rotational force in a machine while countershaft is a jackshaft.
jackshaft
English
Noun
(
en noun)
(
wikipedia jackshaft)
A common mechanical component used to transfer or synchronize rotational force in a machine.
A wheelless axle used to turn the wheels of a locomotive.
Synonyms
* (component relating to rotational force) countershaft