senselessness vs vacuity

senselessness and vacuity both are nouns.

Word	Noun	Adjective	Verb	Adverb
senselessness	Yes	No	No	No
vacuity	Yes	No	No	No

As nouns, senselessness and vacuity are synonyms defined as:

Other synonyms of senselessness include inanity, mindlessness, pointlessness.

senselessness (noun)	vacuity (noun)
total lack of meaning or ideas	total lack of meaning or ideas
	a region that is devoid of matter
	the absence of matter