WordWeb Online

1. Of or relating to or constituting the vitreous humour of the eye
   "the vitreous chamber"
    
2. Relating to or resembling or derived from or containing glass
   "vitreous rocks"; "vitreous silica"
    
3. (of ceramics) having the surface made shiny and nonporous by fusing a vitreous solution to it
   "hard vitreous china used for plumbing fixtures"
   - glassy, vitrified

See also: glass, glazed, shiny, vitreous humor [US]

Encyclopedia: Vitreous