jillion vs zillion

jillion and zillion both are nouns.

Word	Noun	Adjective	Verb	Adverb
jillion	Yes	No	No	No
zillion	Yes	Yes	No	No

As nouns, jillion and zillion are synonyms defined as:

Other synonyms of jillion include bazillion, billion, gazillion, million, trillion.

jillion (noun)	zillion (noun)
a very large indefinite number (usually hyperbole)	a very large indefinite number (usually hyperbole)

jillion (adjective)	zillion (adjective)
	very large indeterminate number