A person who is obsessed with the Harry Potter franchise to the point of planning their entire life around the release of the next Harry Potter movie or book.
Example 1

Friend 1: I'M DROPPING EVERYTHING TO GO TO THE MIDNIGHT PREMIERE OF HARRY POTTER AND THE DEATHLY HALLOWS TONIGHT!!
Friend 2: You are such a Harry Potthead.

Example 2:

Girlfriend: Hey, I'm really in the mood tonight, if you know what I mean...
Boyfriend: Not now, I'm watching all of the previous 6 Harry Potter movies before the new one opens!
Girlfriend: Why am I dating a Harry Potthead??
by damnteenager108 November 18, 2010
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