It's likely that you're encountering this phrase in a specific context, and the meaning could be dependent on that. Here are some possibilities:
* A distinction within a publication: It might be a way to differentiate the main editorial piece from other opinion pieces or letters to the editor within a publication.
* A specific type of editorial: Perhaps it's used to indicate an editorial that's focused on a specific issue, or written in a particular style, like being particularly argumentative or analytical.
* A technical writing term: In technical writing, "editorial proper" could refer to the main body of an editorial, as opposed to things like the title, author information, or any accompanying graphics.
To understand the meaning of "editorial proper" in your context, please provide more information:
* Where did you encounter this term? (e.g., a textbook, a website, a publication)
* What was the context of the term? (e.g., a list of types of editorials, a description of a specific publication)
Once you provide more context, I can give you a more accurate and helpful response.