Definition:Parallelepiped

Definition
A parallelepiped is a polyhedron formed by three pairs of parallel planes:


 * Parallelepiped.png

In the above example, the pairs of parallel planes are:


 * $ABCD$ and $HGFE$
 * $ADEH$ and $BCFG$
 * $ABGH$ and $DCFE$

Historical Note
The term parallelepiped is never actually defined by Euclid, although he specifies the concept:

The proposition that follows this one uses the term in a proof.

Linguistic Note
The word parallelepiped is divided into syllables and stressed as par-al-lel-ep-i-ped.

The pronunciation par-al-lel-e-pi-ped is technically incorrect.

The occasionally-seen spelling parallelopiped is also considered incorrect.