I've likely said it before, but absolutely the best word for "the day after tomorrow" is the Georgian one, ზეგ (zeg). What could be more succinct?

And can you enlighten us what "zeg" means when literally translated (that is if it can be)?
And can you enlighten us what "zeg" means when literally translated (that is if it can be)?
Ha. Literally translated, "zeg" means "the day after tomorrow." Full stop. There is no deeper meaning, no (known) etymological obscurities to unravel. (Since Georgian is a linguistic isolate, unrelated to any major language, many of its sources remain obscure.) It is what it is: a convenient way to refer to the near, but not immediate, future.
Dutch= overmorgen. Clearly a cognate of 'overmorrow'.
Still very much in use.
'eergisteren' is the day before 'gisteren' (yesterday).

Interesting... the obsolete antonym of overmorrow is ereyesterday. Prefix seems similar to the Dutch version.
I can't believe that the hobbits didn't talk about overmorrow in The Lord of the Rings. It sounds exactly like a common hobbit term, just like "second breakfast."