Source : Webster's Revised Unabridged Dictionary (1913)

Plutonian \Plu*to"ni*an\, a. [L. Plutonius, Gr. ?: cf. F.
   plutonien.]
   Plutonic. --Poe.

Plutonian \Plu*to"ni*an\, n. (Geol.)
   A Plutonist.

Source : WordNet®

Plutonian
     adj : of or relating to or characteristic of Hades or Tartarus
           [syn: {Hadean}, {Tartarean}]