When your hairline looks awful or ghastly.
This may even cause others who see it to have a nauseating effect due to witnessing such an atrocity.
Drew aka Drewbacca perfectly exemplifies this definition:
His hairline resembles a staircase, now this wasn't done on purpose hence the "Fucked Up Hairline"

Visual Evidence:
Exhibit A:
http://farm4.static.flickr.com/3485/3183251697_f95103f461.jpg
Exhibit B:
http://farm4.static.flickr.com/3128/3178603647_11c3f91e80.jpg
by Hypebeast2009 January 10, 2009
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