If someone says they're 'not about that life' it means that they don't or won't do something relating to that subject. It can be used in a variety of contexts and can be about a lot of things but it mostly used to reject someone inviting you to do something because you don't agree with it/don't like what they're doing/just don't want to.

It can also be edited to fit the purpose more by adding in a word before the word life to describe what kind of life said person is not about.
Example 1-
Person 1: Hey, I'm having a Sexy Party this weekend, wanna come?
Person 2: Nah, I'm not about that life. I'm sure you'll be coming enough for the both of us.

Example 2-
Person: Want to take a picture with me?
Person 2: Nope, I'm not about that selfie life.
by notaboutthatlife December 28, 2013
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A phrase very commonly used by rappers to describe their lifestyle (thug lyfe). To be about that life means to live a certain kind of way.
She claim she bad, but she ain't really about that life. She's a photothot.

Most these rappers flashing guns but they ain't really about that life
by Chukssss June 29, 2015
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Not being a type of something, something you're not about.
Person 1: Wanna come to the library?
Person 2: Nah, I'm not about that life.
by ImTheMan23 January 24, 2016
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When you're young, flashy, and interested in the finer things, such as: fashion, traveling, cars, girls, and high-grade marijuana.
"I'm about that life, nigga
Put you in the game, let you meet my wife, nigga" - Fabolous
by mwbar January 21, 2012
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A. Being in harmony and peace within yourself and your surroundings.
B. Doesn't give a shit about what others say and think.
It's Friday and I'm about that life

He just got a blow job in the car, he about that life.
by Jibz December 20, 2012
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Having or desiring an ostentatious lifestyle, especially involving sex, drugs, and violence.
I'm about that life, so it's no biggie to me. I've been in these streets before.
by GaderKadoz December 20, 2020
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not living life to the fullest, not taking chances, being basic
bob couldnt go to the party tonight; bill told him to sneak out, bob said no.... BOB IS NOT ABOUT THAT LIFE
by weaboutthatlife July 4, 2011
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