The Collaborative International Dictionary of English v.0.48:

Goth \Goth\, n. [L. Gothi, pl.; cf. Gr. ?]
   1. (Ethnol.) One of an ancient Teutonic race, who dwelt
      between the Elbe and the Vistula in the early part of the
      Christian era, and who overran and took an important part
      in subverting the Roman empire.
      [1913 Webster]

   Note: Under the reign of Valens, they took possession of
         Dacia (the modern Transylvania and the adjoining
         regions), and came to be known as Ostrogoths and
         Visigoths, or East and West Goths; the former
         inhabiting countries on the Black Sea up to the Danube,
         and the latter on this river generally. Some of them
         took possession of the province of Moesia, and hence
         were called Moesogoths. Others, who made their way to
         Scandinavia, at a time unknown to history, are
         sometimes styled Suiogoths.
         [1913 Webster]

   2. One who is rude or uncivilized; a barbarian; a rude,
      ignorant person. --Chesterfield.
      [1913 Webster]

WordNet (r) 3.0 (2006):

Goth
    n 1: a crude uncouth ill-bred person lacking culture or
         refinement [syn: peasant, barbarian, boor, churl,
         Goth, tyke, tike]
    2: one of the Teutonic people who invaded the Roman Empire in
       the 3rd to 5th centuries