Source : Webster's Revised Unabridged Dictionary (1913)

Vitrification \Vit`ri*fi*ca"tion\, n. [See {Vitrify}.]
   Same as {Vitrifaction}. --Sir T. Browne. Ure.

Source : WordNet®

vitrification
     n 1: a vitrified substance; the glassy result of being vitrified
     2: the process of becoming vitreous