being vs preexistence

being and preexistence both are nouns.

Word	Noun	Adjective	Verb	Adverb
being	Yes	No	No	No
preexistence	Yes	No	No	No

As nouns, preexistence is a hyponym of being; that is, preexistence is a word with a more specific, narrower meaning than being:

being (noun)	preexistence (noun)
a living thing that has (or can develop) the ability to act or function independently	existing in a former state or previous to something else
the state or fact of existing