Boo boo and boo typically don't have the same meaning. boo boo can refer to:

1) (noun) a mistake, usually a small one, but humorously a large mistake.
2) (noun) a small injury such as a cut or a bruise, used for children but humorously used for adults as well.
3) (verb; noun) the act of defecation (going poo), or the poo itself.
4) (adjective) general unattractiveness, lack of quality or badness.

Because of it is a relatively simple and humorous sounding word, it may have many more colloquial meanings within families, friends or groups.
1) Jeffrey dropped a plate and it broke, he made a boo boo.

2) Timmy fell off his bike and got a boo boo, he ran home to mommy so she could kiss it and make it better.

3) "Lets stop at the next restroom we find. I gotta go boo boo"

or

"I made a stinky boo boo!"

4) "Have you seen Duane's new car?" "Haha yea, that shit is boo boo!"
by Laqueshus June 5, 2009
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A sensitive, lovable 5'11" male who walks around like he is 10FT tall. Often comes off very confident, and refers to himself as a BEAR.

He loves the phrase " DON'T POKE THE BEAR!".

He poses as a tough guy but the reality is, he's just a cub ("Boo-Boo") in a Bears clothing.

A BOO-BOO is very easy to love, and make fun of. He also got jokes
"BOO-BOO"cried when I used him for sex, and then told him to Bounce
by JHut June 26, 2012
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An adjective (with emphasis on the second 'boo') used to describe anything and everything that sucks, whether it be a bad situation, something disappointing, etc, but isn't extremely terrible. Usually placed at the beginning or end of a sentence.
Jesse, I changed the date for my party just for you and now you can't come? That's boo boo.

Ahh, boo boo! I forgot to write my paper!!!

Seriously? He gave us homework on the first day of school?! Boo boo.
by VonKeiss August 24, 2008
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1) Another term for feces or defecation

2) Using as an adjective to describe poor mood or feeling badly
1) Did you see how much booboo was in that diaper?

2) I feel like boo boo! I think I may have the flu
by Wizzyforreal November 28, 2011
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