tank engine

plural tank engines

1. A steam locomotive that carries its fuel and water containers on the locomotive frames rather than in a separate tender.

   The 2-4-2 tank engines of the Great Eastern and the London and North Western were simply adaptations of 2-4-0 main-line engines; the 0-4-4 tank engine owed its parentage to the archaic 0-4-2 mixed traffic.

   1952, Cuthbert Hamilton Ellis, The Beauty of Old Trains, page 117

   1 more example

   Train journeys were not long in terms of distance, and having regard to these factors, the tank engine inevitably preponderated. [...] Among tank engines, the 0-6-2 wheel arrangement was by far the most numerous, there being nearly 450 of this arrangement, which offers the advantage of good power and adhesive weight, coupled with adequate tank and bunker capacity, within a limited compass.

   1939 September, D. S. Barrie, “The Railways of South Wales”, in Railway Magazine, page 161

   Synonyms: tank locomotive