The empty hollow feeling you get in your head after too much boozing, smoking, or working at Swiss Colony.
Man T dog I gots the cavebrain so bad I can't even think.
by Mow-ree May 13, 2004
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An individual who believes in the benefits of paleo nutrition
Cavebrain dined on his pinecone with glee. He sure was a lucky boy.
by Eric Geoffries January 16, 2017
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