(in a lathe) one of several gears for driving the headstock at various speeds.
Words nearby back gear
OTHER WORDS FROM back gearback·geared, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020
Examples from the Web for back gear
Referring again to Fig. 494, g′ is the pinion to drive the back gear while g receives motion from the back-gear pinion.Modern Machine-Shop Practice, Volumes I and II|Joshua Rose