gas oven vs cremation chamber

gas oven and cremation chamber both are nouns.

Word	Noun	Adjective	Verb	Adverb
gas oven	Yes	No	No	No
cremation chamber	Yes	No	No	No

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

gas oven: a cremation chamber fueled by gas
cremation chamber: a furnace where a corpse can be burned and reduced to ashes

Other hypernyms of gas oven include crematorium, crematory.

gas oven (noun)	cremation chamber (noun)
a domestic oven fueled by gas	a furnace where a corpse can be burned and reduced to ashes
a cremation chamber fueled by gas