graveyard vs burial ground

graveyard and burial ground both are nouns.

Word	Noun	Adjective	Verb	Adverb
graveyard	Yes	No	No	No
burial ground	Yes	No	No	No

As nouns, graveyard and burial ground are synonyms defined as:

Other synonyms of graveyard include burial site, burying ground, cemetery, memorial park, necropolis.

graveyard (noun)	burial ground (noun)
a tract of land used for burials	a tract of land used for burials