Hereafter means from this time forward, or in the future after a particular point. When a judge announces “The defendant shall hereafter be known as innocent,” she means from now on. When a contract states “The company, hereafter referred to as 'the Seller,'” it's setting up a shorthand that will be used for the rest of the document.

The word often appears in formal or legal writing. You might see it in a school handbook: “Students who violate this rule shall hereafter receive a detention.” It means the new consequence applies going forward, not to past violations.

Hereafter can also mean the afterlife or a future existence beyond death. When people speak of “the hereafter,” they're referring to whatever might come after our lives end. Different religions and philosophies have different beliefs about the hereafter.

In everyday conversation, people usually say “from now on” instead. But hereafter still shows up in legal documents, formal announcements, and writing where precision matters.