vitrify
    v 1: change into glass or a glass-like substance by applying
         heat
    2: undergo vitrification; become glassy or glass-like

Vitrify \Vit"ri*fy\, v. t. [imp. & p. p. Vitrified; p. pr. &
   vb. n. Vitrifying.] [F. vitrifier; L. vitrum glass +
   -ficare to make. See Vitreous, -fy.]
   To convert into, or cause to resemble, glass or a glassy
   substance, by heat and fusion.
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Vitrify \Vit"ri*fy\, v. t.
   To become glass; to be converted into glass.
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         Chymists make vessels of animal substances, calcined,
         which will not vitrify in the fire.      --Arbuthnot.
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