word choice - Henceforth vs. hereinafter - English Language Usage . . . "henceforth": refers to a moment in time (from now on; in the future) So, to answer your question, "hereinafter" (or "herein after") is most likely what you'd be using for your purposes Both are used only in legal documents, otherwise considered archaic
henceforth-meaning-usage-examples-how-to-use The word henceforth is an adverb used to indicate that something will start from now or from a specific time and continue into the future It means from now on from this time forward