noun, adverb
four days from now; five days from now (regional)
Refers to the day four days after today in standard usage, but in some regions it means five days from now. Used both as a noun and adverbially.
五明後日は友達の誕生日だ。
Four days from now is my friend's birthday.
地域によっては、五明後日が五日後を指すこともある。
Depending on the region, 五明後日 can refer to five days from now.
Compound of 五 (go, 'five') and 明後日 (asatte, 'day after tomorrow'), literally 'five days after tomorrow', though the actual meaning is four days from now in most regions. The regional variation may stem from different counting traditions.