Brake cylinder and Piston chamber

Brake cylinder noun - A cylinder that contains brake fluid that is compressed by a piston.

Piston chamber and brake cylinder are semantically related. In some cases you can use "Piston chamber" instead a noun phrase "Brake cylinder".

Piston chamber noun - A chamber within which piston moves.

Brake cylinder and piston chamber are semantically related. Sometimes you can replace phrase "Brake cylinder" with "Piston chamber", this phrases are similar.