What is Third Nipple?
1.
A mole often directly between the two real nipples. Completely useless as a nipple.
Carlos has a third nipple!
See
2.
Used in the phrase "Don't take it to the third nipple!"
The "third nipple" is non-existant because it's one too many body parts we need, so it's used to refer to when someone is over reacting to something or is about to say something that's exaggerative (<-is that a word?).
"Oh my GOD!! I'm going to kill you! You lil' sonuvabitch!! Why I ought.."
"Whoa dude, don't take it to the third nipple!"
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3.
something completely useless.
I need cancer like I need a third nipple.