The Collaborative International Dictionary of English v.0.48:

Inside \In"side`\, a.
   1. Being within; included or inclosed in anything; contained;
      interior; internal; as, the inside passengers of a
      stagecoach; inside decoration.
      [1913 Webster]

            Kissing with inside lip.              --Shak.
      [1913 Webster]

   2. Adapted to the interior.
      [1913 Webster]

   Inside callipers (Mech.), callipers for measuring the
      diameters of holes, etc.

   Inside finish (Arch.), a general term for the final work in
      any building necessary for its completion, but other than
      unusual decoration; thus, in joiner work, the doors and
      windows, inside shutters, door and window trimmings,
      paneled jams, baseboards, and sometimes flooring and
      stairs; in plaster work, the finishing coat, the cornices,
      centerpieces, etc.,; in painting, all simple painting of
      woodwork and plastering.

   Inside track, the inner part of a race course; hence,
      colloquially, advantage of place, facilities, contacts,
      etc., in competition.
      [1913 Webster]

WordNet (r) 3.0 (2006):

inside track
    n 1: a favorable position in a competition; "the boss's son had
         the inside track for that job"
    2: the inner side of a curved racecourse