Symbolic parallelepiped region; stays unevaluated and is consumed by region functions (RegionDimension/RegionMeasure/…)
Parallelepiped[p, {v1, …, vk}]
Graphics[Parallelepiped[{0, 0}, {{1, 0}, {1, 1}}]]
→ -Graphics-Graphics3D[Parallelepiped[{0, 0, 0}, {{1, 0, 0}, {1, 1, 0}, {0, 1, 1}}]]
→ -Graphics3D-Graphics3D[Parallelepiped[{0, 0, 0}, {{1, 1, 0}, {1, 2, 3}}]]
→ -Graphics3D-