BSL Chemistry Glossary - solid - definition
Definition: We can sign solid in two ways to show the way it looks and feels or to show the particles which make it. The particles are too small for us to see. But if we could look at them we would see they are closely packed and vibrating. We can't see or feel particles, they're too small. We can't compress a solid because the particles are so close together. A solid is hard because the particles are closely packed together.