Everything written after 9 p.m. local standard time (emails, texts, Facebook messages, etc.) must be approved by an objective party in order to prevent the sender's potentially profound regret the following morning.
Example A
Mike: I still love her, man. That's it, I'm sending her a text right now to tell her.
Aaron: Whoa there. It's 11:30, the Rule of 9 is in effect. Hand over the iPhone.
Example B
Alison: My boss is such a bitch. I can't take it anymore, I'm sending in my resignation right now.
Jill: Rule of 9; back away from the laptop. You'll thank me in the morning.
Mike: I still love her, man. That's it, I'm sending her a text right now to tell her.
Aaron: Whoa there. It's 11:30, the Rule of 9 is in effect. Hand over the iPhone.
Example B
Alison: My boss is such a bitch. I can't take it anymore, I'm sending in my resignation right now.
Jill: Rule of 9; back away from the laptop. You'll thank me in the morning.
by PookiePookiePookie Mama July 26, 2011
Get the Rule of 9mug. by MissNoodles June 23, 2006
Get the Rule 9mug. What if I get into something i can't get out of. ....
Rule 9 : always carry a knife, you can cut yourself out of anything.
Rule 9 : always carry a knife, you can cut yourself out of anything.
by nothing is real May 4, 2016
Get the rule 9mug. 
There is no rule 11
by Dr. Crowley January 24, 2010
Get the Rule 9mug. 
The wind was howling and the rain bounding the tarmac, but a baddass bunch of rule 9ers carried on pedalling through the shitstorm that is the British summertime.
by AD828321 June 7, 2020
Get the Rule 9mug.