It's actually the spot between your eyebrows where you would have a horn, were you a unicorn. Humorous in context because of its suggestive nature, even though its root meaning is quite innocent.
Person 1: I'm actually not that hot in my unicorn area.
Person 2: WTF?!

She was sweating profusely from her unicorn area because it was 100 degrees out.
by Rainalot_ February 20, 2010
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