DuckCorp Dico

Found one definition

1.                 From The Jargon File (version 4.4.7, 29 Dec 2003):
                   
   
   
                   
                     
   hair
    n.
       [back-formation from hairy] The complications that make something hairy.
       “Decoding TECO commands requires a certain amount of hair.” Often seen in
       the phrase infinite hair, which connotes extreme complexity. Also in
       hairiferous (tending to promote hair growth): “GNUMACS elisp encourages
       lusers to write complex editing modes.” “Yeah, it's pretty hairiferous all
       right.” (or just: “Hair squared!”)