The Collaborative International Dictionary of English v.0.48:

Gnome \Gnome\, n. [F. gnome, prob. fr. Gr. gnw`mon one that
   knows, a guardian, i. e., of the treasures in the inner parts
   of the earth, or fr. ? intelligence, both fr. gnw^nai,
   gignw^skein, to know. See Know.]
   1. An imaginary being, supposed by the Rosicrucians to
      inhabit the inner parts of the earth, and to be the
      guardian of mines, quarries, etc.
      [1913 Webster]

   2. A dwarf; a goblin; a person of small stature or misshapen
      features, or of strange appearance.
      [1913 Webster]

   3. (Zool.) A small owl (Glaucidium gnoma) of the Western
      United States.
      [1913 Webster]

   4. [Gr. ?.] A brief reflection or maxim. --Peacham. Gnomic