grave mound vs burial mound

grave mound and burial mound both are nouns.

Word	Noun	Adjective	Verb	Adverb
grave mound	Yes	No	No	No
burial mound	Yes	No	No	No

As nouns, grave mound and burial mound are synonyms defined as:

grave mound and burial mound: (archeology) a heap of earth placed over prehistoric tombs

Other synonyms of grave mound include barrow, tumulus.

grave mound (noun)	burial mound (noun)
(archeology) a heap of earth placed over prehistoric tombs	(archeology) a heap of earth placed over prehistoric tombs