Source : Webster's Revised Unabridged Dictionary (1913)

Hercynian \Her*cyn"i*an\, a. [L. Hercynia silva, Hercynius
   saltus, the Hercynian forest; cf. Gr. ? ?.]
   Of or pertaining to an extensive forest in Germany, of which
   there are still portions in Swabia and the Hartz mountains.