Marmalade boxes are containers typically used to store and serve marmalade. If you're looking for synonyms for this word, there are a few options to consider. One possibility is simply to refer to it as a "jam jar" or "preserves container". Another option is to use more generic terms like "container" or "vessel", both of which can be applied to various types of jars or boxes. If you're looking for something more specific, you might consider terms like "apothecary jar" or "glass jar with lid", which may be more decorative or upscale than a simple marmalade box.