4-8-2 noun1 •Under the Whyte notation system, a steam locomotive that has four leading wheels arranged in a leading truck, eight coupled driving wheels and two trailing wheels in a trailing truck.Most Canadian engines are black. [...] The C.N.R. has only three classes of non-black engines, the "6400s", the later 4-8-2s and the 4-6-4s. — 1959 forms4-8-2s