Related Clues:
- Sturdily built
- Chock-a-block
- Parallelepiped, e.g.
- Densely built
- Concrete or reilable
- Firm, strong
- Three-dimensional shape, not hollow
- Not hollow, the same throughout
- Thus the top has not got a hole in it
- Thus it's not a hollow top
- Thus, no hollow cover
- Thus on the cover there's no hollow
- Not a liquid or a gas
- Not liquid or gaseous
- Type of geometry