a box of some sort which is placed on the head and is rotated vigorously in order to ruin the hairstyle of the victim- thus giving them A blockhead.

There is also blockhead resistant gel that can be worn to protect ones hairstyle.
Oh that Moonhead has got a proper blockhead after we got him with the blockhead machine! he's been merked
by Sie n Grev September 26, 2007
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