Glossiness

Depending on the smoothness of a surface, it will scatter the reflected light in different directions. Look at this picture of the two bottles. One is glass and the other is a wood-like texture. The glass surface is very smooth. So the reflected light is hardly scattered and looks shiny. The woody surface is rough and scatters the light in all directions creating a non-shiny, ‘matte’ surface.

For a matte surface, the amount of scatter is more. There can still be highlights, but they will be spread out over a large region. For a smooth or ‘glossy’ surface, the scatter is very little. The highlights, in this case, will be very sharp and shiny. This property is ‘glossiness’.

In this picture, you can compare a Glossy and matte surface

So the highlights on the surface of the object will be a combination of its specularity and glossiness.

Another property that goes somewhat hand in hand with a surface with high specularity and glossiness is it’s ability to reflect it’s surrounding, This property is Reflection.