noun, masculine/pa.ʁa.le.le.pi.pɛd/plural: parallélépipèdes
parallélépipède is masculine in French.
parallelepiped
“un parallélépipède rectangle” — a rectangular cuboid
Related: parallélépipédique
Borrowed from Latin parallēlepipedum, itself a borrowing from Ancient Greek παραλληλεπίπεδον (parallēlepípedon).