hereafter vs hereinafter

hereafter is a noun but hereinafter is not a noun.

Word	Noun	Adjective	Verb	Adverb
hereafter	Yes	No	No	Yes
hereinafter	No	No	No	Yes

As adverbs, hereafter and hereinafter are synonyms defined as:

hereafter and hereinafter: in a subsequent part of this document or statement or matter etc.

Other synonyms of hereafter include hereunder.

hereafter (noun)	hereinafter (noun)
the time yet to come
life after death

hereafter (adverb)	hereinafter (adverb)
in a subsequent part of this document or statement or matter etc.	in a subsequent part of this document or statement or matter etc.
following this in time or order or place; after this
in a future life or state