In a living arrangement that contains 3 lease holders in one household, it is predetermined that power is distributed equally into 33% per person. 66/33 is when two of the roommates start to date and their decision making process becomes parallel, making the power distribution 66% to 33%. This makes the third wheel in the household unable to win any argument against the couple. A 66/33 often results in the third party moving out, or being kicked out of said living arrangement due to being outnumbered.
Person 1: "Yeah, I just moved out of my apartment the other day."

Person 2: "Why is that?"

Person 1: "66/33, she was sleeping with my other roommate and they wanted it to be a 'couples' household."
by Mactastic1218 June 16, 2011
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"Send nudes" but on a Nokia Keypad.
Guy: 7777 33 66 3 66 88 3 33 7777
Girl: What?
Guy: Send nudes
Girl: ...
by Friendly Zhark August 18, 2019
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