The Collaborative International Dictionary of English v.0.48:

Fogy \Fo"gy\, n.; pl. Fogies.
   1. A dull old fellow; a person behind the times,
      over-conservative, or slow; -- usually preceded by old; an
      old fogy. [Written also fogie and fogey.] [Colloq.]
      [1913 Webster]

            Notorious old bore; regular old fogy. --Thackeray.
      [1913 Webster]

   Note: The word is said to be connected with the German vogt,
         a guard or protector. By others it is regarded as a
         diminutive of folk (cf. D. volkje). It is defined by
         Jamieson, in his Scottish Dictionary, as "an invalid or
         garrison soldier," and is applied to the old soldiers
         of the Royal Hospital at Dublin, which is called the
         Fogies' Hospital. In the fixed habits of such persons
         we see the origin of the present use of the term. --Sir
         F. Head.
         [1913 Webster]

   2. (Mil.) In the United States service, extra pay granted to
      officers for length of service. [Colloq.]
      [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

fogy
    n 1: someone whose style is out of fashion [syn: dodo, fogy,
         fogey, fossil]

Moby Thesaurus II by Grady Ward, 1.0:

49 Moby Thesaurus words for "fogy":
   Methuselah, antediluvian, antique, back number, conservationist,
   conservatist, conservative, dad, diehard, dodo, dotard, elder,
   fossil, fud, fuddy-duddy, granny, has-been, laudator temporis acti,
   longhair, matriarch, mid-Victorian, mossback, old believer,
   old crock, old dodo, old fart, old fogy, old liner, old man,
   old poop, old school, old woman, old-timer, patriarch, pop, pops,
   reactionary, regular old fogy, relic, right-winger, rightist,
   senile, square, standpat, standpatter, starets, stick-in-the-mud,
   traditionalist, ultraconservative