"Vitreous" refers to a glass-like quality or appearance, often used to describe materials that are smooth, shiny, and transparent. In the context of ceramics, vitreous materials are those that have been fired at high temperatures, resulting in a non-porous surface that is resistant to water and stains. This property makes vitreous ceramics ideal for items like tiles and dinnerware. In the field of biology, "vitreous" can also describe the vitreous humor, a clear gel-like substance found in the eye. This gel fills the space between the lens and the retina, helping to maintain the eye's shape and providing support to the retina. The vitreous humor is crucial for proper vision and overall eye health.