“anachronism”

• a thing belonging or appropriate to a period other than that in which it exists, especially a thing that is conspicuously old-fashioned:
  the town is a throwback to medieval times, an anachronism that has survived the passing years.
• the action of attributing something to a period to which it does not belong:
  it is anachronism to suppose that the official morality of the age was mere window dressing.

— Oxford Dictionary of English