Source : Webster's Revised Unabridged Dictionary (1913)

Goblin \Gob"lin\, n. [OE. gobelin, F. gobelin, LL. gobelinus,
   fr. Gr. ? knave, a mischievous goblin; or cf. G. kobold, E.
   kobold, cobalt, Armor. gobilin an ignis fatuus, goblin.]
   An evil or mischievous spirit; a playful or malicious elf; a
   frightful phantom; a gnome.

         To whom the goblin, full of wrath, replied. --Milton.

Source : WordNet®

goblin
     n : (folklore) a small grotesque supernatural creature that
         makes trouble for human beings [syn: {hob}, {hobgoblin}]