An arrangement in three-dimensional space of n congruent cubes joined to one another by at least one of their faces.
- A polycube formed by joining 2 cubes is called a dicube.
- Polycubes formed by joining 3 cubes are called tricubes. There are 2 tricubes.
- Polycubes formed by joining 4 cubes are called tetracubes. There are 8 tetracubes.
- Polycubes formed by joining 5 cubes are called pentacubes. There are 29 pentacubes.
- Polycubes formed by joining 6 cubes are called hexacubes. There are 166 hexacubes.