Source : Webster's Revised Unabridged Dictionary (1913)

Onomasticon \On`o*mas"ti*con\, n. [NL., fr. Gr. ? (sc.?), fr. ?.
   See {Onomastic}.]
   A collection of names and terms; a dictionary; specif., a
   collection of Greek names, with explanatory notes, made by
   Julius Pollux about A.D.180.

Source : WordNet®

onomasticon
     n : a list of proper nouns naming persons or places