When the substance of what your saying is so unimportant that if someone did not hear you, and they asked you to say it again, you would tell them "oh, no i'm just talking out my ass"
Joe:

Yeah John was actually helping me move the other day. He was telling me that his family went to Santa Barbara for the winter to stay with a couple of friends and it's actually funny because i was thinking about taking the wife and kids down there.

Eric:
.. hmm huh, sorry, what you say?

Joe:
Ah nah don't worry about it, i'm just talking out my ass
by Jose Boro February 3, 2017
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Something you say when you see something really cool, or a hot girl walks by. You can say it even if you never talked about the subject before.
Two dudes sitting around.
15 minutes of silence
Dude #1: "Look at that chick!"
Dude #2: "That's what I'm talkin about!"
by whodey June 16, 2004
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Dude 1: "Dude, check out the size of that cheeseburger!"
Dude 2: "Now, that's what I'm talking about!"
by Fronck June 2, 2008
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Etymological note: This phrase can be heard in a recording of the (ca.) 1929 Fats Waller song "The Joint is Jumping".
"Get rid of that pistol, yeah, get rid of it... yeah... ha ha... that's what I'm talking about..." (from abovementioned recording, spoken)
by Tyranny Sue July 11, 2008
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"Now that's what I'm talking about'!

'A catch phrase' commonly used to express 'enthusiastic support' for a particular 'subject/or subject matter'.

(With more of an emphasis placed on the word 'that's')
*acronym/abbreviated form: NTWITA or TWITA 'That's What I'm Talking About'.
Example:-

A guy just opened his first pay check- and he discovered, that the amount of money enclosed, was a lot more than he was expecting!

-> so he say's (while nodding his head in approval)~ 'Now that's what i'm talking about' !
by Stump cap November 24, 2013
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