Kerem Bürsin this is for you:
A mysterious period in time, where SCK fandom is still trying to find out when that tomorrow is gonna come, and according to Kerem Bürsin he has no such memory of “tomorrow”.

(I guess he got a lil bit too much into character and lost his memory too, who knows, neyse Kerem LIVE NERDE???)

The day that according to Annie, the sun’ll be out and tomorrow will always be there. Unless of course you die. Then no tomorrow for you I guess.

(University setting) the lnext time a class will meet, whether or not that is the day following today.

Maybe the next day, or maybe a week from today. It's a generic term for the future, ≥ 1 day and ≤ 1 week.

A sorry excuse for fat people to not start a diet

the day after today ... What happens after its midnight.

A term used within game development, especially MMORPG's. It's meaning is as loose as from actually "The day after today" to "sometime in a undistinguishable and intangible time that it is possible none of us will live to see."