hairy

hairy adj.  1. Annoyingly complicated.  "{DWIM} is
   incredibly hairy."  2. Incomprehensible.  "{DWIM} is
   incredibly hairy."  3. Of people, high-powered, authoritative,
   rare, expert, and/or incomprehensible.  Hard to explain except in
   context: "He knows this hairy lawyer who says there's nothing to
   worry about."  See also {hirsute}.

   A well-known result in topology called the Brouwer Fixed-Point
   Theorem states that any continuous transformation of a surface into
   itself has at least one fixed point.  Mathematically literate
   hackers tend to associate the term `hairy' with the informal
   version of this theorem; "You can't comb a hairy ball smooth."

   The adjective `long-haired' is well-attested to have been in
   slang use among scientists and engineers during the early 1950s; it
   was equivalent to modern `hairy' senses 1 and 2, and was very
   likely ancestral to the hackish use.  In fact the noun
   `long-hair' was at the time used to describe a person satisfying
   sense 3.  Both senses probably passed out of use when long hair
   was adopted as a signature trait by the 1960s counterculture,
   leaving hackish `hairy' as a sort of stunted mutant relic.