1 definition by GhilliEwok

A person who is mad about death and all things dark, Usually male he sits alone on a dark room and has very few close friends. Form the words : Madhatter and killing. Also slang for a long killstreak on a video game.
Oh my god killhatter is so Dark.

Wow, that guys is pulling a killhatter on this life
by GhilliEwok June 25, 2013
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