What is 1week1day?
The 1week1day anniversary of one's birthday occurs exactly one week and one day (exactly 8 days) after a one's real birthday. It is highly useful when you've forgotten to wish someone a happy birthday on their actual birthday because you are a jerk and only realize it an entire week and a day later.
Of course I didn't forget your birthday! I just wanted to wait till the 1week1day anniversary to wish you!