Uhh, wisdom, like yo back teeth
A wisdom tooth, in humans, is any of the usual four third molars. Wisdom teeth usually appear between the ages of 17 and 25. Most adults have four wisdom teeth, but it is possible to have fewer (hypodontia), or more, in which case they are called supernumerary teeth. Wisdom teeth commonly affect other teeth as they develop, becoming impacted or “coming in sideways.” They are often extracted when this occurs.
Big boi is referring to wisdom as: The quality of having experience, knowledge, and good judgment; the quality of being wise.
Big Boi is saying that they are dummies and he gots wisdom, like his back teeth. Its wordplay with double meaning.
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