1.Definition: (of ceramics) having the surface made shiny and nonporous by fusing a vitreous solution to it

"Hard vitreous china used for plumbing fixtures"

Related Adjective(s):glassy, vitrified

2.Definition: of or relating to or constituting the vitreous humor of the eye

"The vitreous chamber"

3.Definition: relating to or resembling or derived from or containing glass

"Vitreous rocks", "Vitreous silica"