The 2-8-2 represents the wheel arrangement of two leading wheels on one axle, usually in a leading truck, eight powered and coupled driving wheels on four axles and two trailing wheels on one axle, usually in a trailing truck. This configuration of steam locomotive is most often referred to as a Mikado, frequently shortened to Mike.

The 2-8-2 was one of the more common configurations in the first half of the 20th century, before diesel locos gained in popularity. Between 1917 and 1944, nearly 2,200 of this type were constructed by the American Locomotive Company (ALCO), Lima Locomotive Works and Baldwin, based on designs by the United States Railroad Administration (USRA).