Source : Webster's Revised Unabridged Dictionary (1913)

Cranioclasm \Cra"ni*o*clasm\ (kr?"n?-?-kl?z'm), n. [Cranium +
   Gr. ??? to break.] (Med.)
   The crushing of a child's head, as with the cranioclast or
   craniotomy forceps in cases of very difficult delivery.
   --Dunglison.