Source : Webster's Revised Unabridged Dictionary (1913)

Genethliac \Ge*neth"li*ac\, n.
   1. A birthday poem.

   2. One skilled in genethliacs.

Genethliac \Ge*neth"li*ac\, a. [L. genethliacus, Gr. ?, fr. ?
   belonging to one's birth, gene`qlh birth, fr. gi`gnesqai to
   be born.]
   Pertaining to nativities; calculated by astrologers; showing
   position of stars at one's birth. --Howell.