BA

Depending on context may stand for 'Bad Ass' , 'Bachelard of Art' or 'Breast Augmentation'. Honestly I have never seen it to be used for 'bad ass' as everyone here seems to be suggesting but there you go.

What should be used for bloating/constipation after BA (breast augmentation) surgery?

You are a real BA (bad ass)

He has recently finished his BA course in photography.

Ba

A term of endearment used between friends. Can be used to signify familiarity, rapport and kinship.
The word Ba came from the root word Boss and went though a series of progressions: Boss - Bowws - Biows - Bia - Ba

What's up Ba!
What the fuck is up Ba!
Ba, Bia, BIIIIAAAA, BA!

Ba

Bah is a word you can say to someone. If your friend for example are telling something random, you say Ba.

Friend: "Yo bro, yesterday I took an insanely big shit."
You say:"Ba"

BA

A badass.

Person 1" Did you see the presidential debate last night?"
Person 2" Yea, Trump was BA"

BA

word/noise constantly yelled by all the best athletes in the world. yelling “BA!” when playing a sport makes you 90% better at that sport.

*player hits volleyball over the net
player: “BA!”
*player scores point
*crowd goes wild

Ba

Something or someone that makes you feel safe.

I never go to sleep without my ba.

Hey ba can you come cuddle with me.

BA

abbreviation of "before anyone"

"he is my ba"