Learn English – Is there such a term as “dinner box”

Dinner is considered to be the "main" or largest meal of the day. Whether it takes place at noon or in the evening is mostly a cultural thing. For instance, many people who grew up in the American South and/or on farms traditionally ate larger meals at noontime to give them the strength to keep working through the afternoon.

Supper is more specifically a lighter evening meal. Rooted in the word "to sup", it comes, again, from farming traditions — many farming families would have a pot of soup cooking throughout the day, and would eat it in the evening — specifically, they would "sup" the soup.

Lunch is almost the midday equivalent of supper — it's also a lighter and less formal meal than Dinner, but is used specifically when referring to a midday meal. So whether you use lunch/dinner or dinner/supper is heavily determined by when your culture traditionally has its largest meal.

Much Later Edit: I happened across this article discussing the agricultural roots of midday dinner and evening supper, just to add a bit more to the conversation.

Interesting question! I don't think a single English word exists for this, at least not one that would be readily understood without explanation. If you want one, you'll have to make it up yourself, and be prepared to explain it. Antiversary, for instance, seems cute and compact, but is readily misinterpretable (a friend suggested to me the other day that an antiversary means one year after a couple breaks up).

But if you're willing to use more than one word, negative-first anniversary seems readily understandable; if I'm going to get married a year from now, it's my negative-first anniversary. Googling "negative one anniversary", "negative anniversary" and so on turns up plenty of hits, suggesting that this is a natural, intuitive way to describe the concept.

More colloquially, I often hear people using T-minus terminology - deriving from the countdowns we've all seen in movies, where rocket scientists say something like "T-minus 5 minutes" to mark the time until launch - when describing an anticipated event. So, for instance, a party that's held 1 year before your college graduation could be your "T-minus 1 year grad party."