4-8-4+4-8-4

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Under the Whyte notation system, a Garratt steam locomotive that is articulated in three parts, with a boiler mounted on the centre frame, and two steam engines mounted in opposite directions on separate frames, one on each end of the boiler, and each engine having a 4-8-4 wheel configuration.