piston chamber vs chamber

piston chamber and chamber both are nouns.

Word	Noun	Adjective	Verb	Adverb
piston chamber	Yes	No	No	No
chamber	Yes	No	Yes	No

As nouns, chamber is a hypernym of piston chamber; that is, chamber is a word with a broader meaning than piston chamber:

piston chamber (noun)	chamber (noun)
a chamber within which piston moves	a natural or artificial enclosed space
	a room used primarily for sleeping
	a room where a judge transacts business
	an enclosed volume in the body
	a deliberative or legislative or administrative or judicial assembly

piston chamber (verb)	chamber (verb)
	place in a chamber