Question

What is the term for matter that does not let any light pass through it, whether it absorbs light, reflects light, or does both?

Answer 1

opaque

Opaque matter is matter that does not let any light pass through it. Matter may be opaque because it absorbs light, reflects light, or does both. Examples of opaque objects are solid wooden doors and glass mirrors. A wooden door absorbs most of the light that strikes it and reflects just a few wavelengths of visible light. A mirror, which is a sheet of glass with a shiny metal coating on the back, reflects all the light that strikes it.