The Collaborative International Dictionary of English v.0.48:

Loadstar \Load"star`\, Lodestar \Lode"star`\, n. [Load, lode +
   star. See Lode.]
   1. A star that leads; a guiding star; esp., the polestar,
      Polaris; also, the constellation containing the pole star,
      the cynosure (Ursa Minor). --Chaucer. " Your eyes are
      lodestars." --Shak.
      [1913 Webster]

            The pilot can no loadstar see.        --Spenser.
      [1913 Webster]

   2. Something that serves as a guide or provides direction; a
      cynosure[2].
      [PJC]

   3. Something that attracts attention or on which the atention
      is fixed; a cynosure[3].
      [PJC] Loadstone

The Collaborative International Dictionary of English v.0.48:

Lodestar \Lode"star`\, n.
   Same as Loadstar.
   [1913 Webster]

WordNet (r) 3.0 (2006):

lodestar
    n 1: guiding star; a star that is used as a reference point in
         navigation or astronomy [syn: lodestar, loadstar]
    2: something that serves as a model or guide [syn: lodestar,
       loadstar]

Moby Thesaurus II by Grady Ward, 1.0:

71 Moby Thesaurus words for "lodestar":
   Aldebaran, Canicula, Dog Star, Hesper, Hesperus, Lucifer,
   North Star, Phosphor, Phosphorus, Polaris, Sirius, Venus, Vesper,
   ambition, artificial magnet, aspiration, bar magnet, basis,
   calling, cause, celestial body, center of attraction,
   center of consciousness, center of interest, comet, consideration,
   cynosure, daystar, electromagnetic lifting magnet, evening star,
   field magnet, fixed stars, focal point, focus, focus of attention,
   goal, ground, guiding light, guiding star, heavenly body,
   horseshoe magnet, ideal, inspiration, intention, living sapphires,
   lodestone, magnet, magnetic needle, magnetite, mainspring, matter,
   morning star, motive, orb, paramagnet, point of convergence,
   polar star, polestar, prime focus, principle, reason, sake, score,
   solenoid, source, sphere, spring, starry host, stars,
   ulterior motive, vocation