Frieze by definition is: a wide horizontal band with painted or sculpted decorations (often near the top of a wall and/or near the ceiling or over a doorway). The most famous Frieze can be found on the Parthenon which is located in Greece.
Expanding on the definition in the context of cabinetmaking, Frieze can be made from hardwood or from engineered materials with a ply, MDF or particle core, with either no face, or veneer face. The purpose of Frieze is to provide a place to nail your face mount crown, much like the top rail of a face frame cabinet.
If you need more information, read our Blog post on Frieze, we dive a lot deeper into the topic there.