Heat exchanger
A device used to exchange heat from one medium to another. Radiators, condensers, and evaporators are all examples of heat exchangers. Heat always moves from the object or medium having the greatest level of heat energy to a medium or object having a lower level.
Aviation Maintenance Technician Handbook — Airframe, p. G-18
Taught in PP-L Procedures, AF-G Concepts, AF-G Procedures, PP-L Concepts, PP-L Quick reference.