sepulture vs burial chamber

sepulture and burial chamber both are nouns.

Word	Noun	Adjective	Verb	Adverb
sepulture	Yes	No	No	No
burial chamber	Yes	No	No	No

As nouns, sepulture and burial chamber are synonyms defined as:

Other synonyms of sepulture include sepulcher, sepulchre.

sepulture (noun)	burial chamber (noun)
a chamber that is used as a grave	a chamber that is used as a grave
the ritual placing of a corpse in a grave