However, depending on the context, you could use words that convey the opposite idea:
* PreScript: If you want to emphasize something happening before the PostScript, you could use this made-up term.
* Preceding Text: This more formally describes anything that comes before a PostScript.
* Main Content: This highlights the primary body of text, contrasting it with a PostScript.
* Body of the Text: Similar to "Main Content," it emphasizes the core text.
Ultimately, the best word to use as an "antonym" will depend on the specific context and what you're trying to emphasize.