Diesel locomotive and Steam engine

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

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

Steam engine noun - External-combustion engine in which heat is used to raise steam which either turns a turbine or forces a piston to move up and down in a cylinder.

Diesel locomotive and steam engine are semantically related. You can use "Diesel locomotive" instead a noun phrase "Steam engine".