pericardial cavity vs pericardial space

pericardial cavity and pericardial space both are nouns.

Word	Noun	Adjective	Verb	Adverb
pericardial cavity	Yes	No	No	No
pericardial space	Yes	No	No	No

As nouns, pericardial cavity and pericardial space are synonyms defined as:

pericardial cavity and pericardial space: the space between the layers of the pericardium that contains fluid that lubricates the membrane surfaces and allows easy heart movement

pericardial cavity (noun)	pericardial space (noun)
the space between the layers of the pericardium that contains fluid that lubricates the membrane surfaces and allows easy heart movement	the space between the layers of the pericardium that contains fluid that lubricates the membrane surfaces and allows easy heart movement