Somebody who knows everything about Harry Potter, obsesses over it and in general stays up until 5am reading a HP book with a torch, or looking up Harry Potter Forums on Google.
A Potterhead is NOT the following:
Someone who pronounces the spells incorrectly. (e.g; instead of ''Avada Kedavra,'' they would pronounce it as ''Abracadabra!'')
Someone who calls Severus, as in Severus Snape, Snape. Just Snape.
A person who ''fangirls/boys'' about them online, but typing like this: ''OMG I LUV HP SOOOO MUCH LIKE OMG TOTES I LUV EM ALL.''
Someone who has only ever watched the films, and hasn't read the books.
Fake Potterhead: I LUV HP!!!!11 <3
Potterhead: Oh yes, of course you do. What's Ron's middle name?
Fake Potterhead: Weasley!!!1
Potterhead: No! It's Ronald Billius Weasley, therefore the middle name is BILLIUS.
Friend: Hey, dude, do you wanna come and check out my new house?
Potterhead: No, no... *too busy watching HP7 Part 2*.