Diesel locomotive and Locomotive engine

Diesel locomotive noun - A locomotive driven by a diesel engine.

Locomotive engine and diesel locomotive are semantically related. In some cases you can use "Locomotive engine" instead a noun phrase "Diesel locomotive".

Locomotive engine noun - A wheeled vehicle consisting of a self-propelled engine that is used to draw trains along railway tracks.

Diesel locomotive and locomotive engine are semantically related. Sometimes you can replace phrase "Diesel locomotive" with "Locomotive engine", this phrases are similar.