The Third Boob is an additional boob to the other two which was originally drawn as a shoulder, but later discovered to be a boob.

It may be ripped off and relocated for a variety of usages: the third eye, the double chin, big and pimple'd nose, the "Hunchback" and the "pregnant lady" (for D+ size), and the penis (for the very small yet elongated boobs).

The Third Boob may also be found in men of an immense size.
Person 1:"Ew you have a huge pimple on your forehead D:"
Person 2:"Nah it's just my third boob."
by God~ October 24, 2009
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