dragbox

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dragbox

Wikipedia

From drag +‎ box.

dragbox (plural dragboxes)

1. (rail transport) A substantial, often cast metal, part of a locomotive to which the coupling mechanism is attached to allow the locomotive to pull a train.
   • 1961 March, C. P. Boocock, “The organisation of Eastleigh Locomotive Works”, in Trains Illustrated, page 163:

     Under British Railways management, a large number of fabricated dragboxes for Class 9 2-10-0s were made at Eastleigh, for use in other Regions' works.

• drag box