My tail is never tucked, so fuck niggas beware when ya buck
When a dog tucks its tail between its legs, it usually means they are afraid or frightened. Big Boi isn’t scared.
The animal imagery continues when Big Boi tells his competitors that they eventually will be bucking at him, natural horse behavior developed in the wild and performed for various reasons. It can be used as a defense mechanism, which makes the most sense for this line.
Also, a buck is more commonly known as a male antlered animal, such as the Milwaukee Bucks of the NBA.
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