adjective / noun
solid
SAH-lid/ˈsɑːlɪd/
Firmly constituted throughout, without empty gaps.
The solid ice cube keeps its shape beside the melted water.

Etymology
Latin solidus joined firmness with wholeness and lack of division. The physical sense preserves that idea of a compact, firm body rather than something fluid.
In context
solid waste is composed of the parts of foods that could not be digested liquid and gaseous waste are byproducts of activities of the body cells
More examples
- Ice is a solid, while water is a liquid.
- The table is solid oak, not wood covered with veneer.
- She gives solid advice that we can trust.
- Draw a solid blue line without any gaps.
Forms
solid · solider · solidest · solids
solidity noun — The quality of being firm and substantial.
solidly adverb — In a firm, compact, or secure manner.