In general, it can be defined as the distance between the two parallel planes restricting the object perpendicular to that direction.

Under the strange illumination here it appeared to form a parallel plane above the floor.

Above, on the bridge, Jesudasyn's imagination drifted along a parallel plane.

More generally, any compact convex body D has one pair of parallel supporting planes in a given direction.

The new building will rise from the sidewalk in three parallel planes, like huge steps.

All have their vertices in parallel planes and are therefore prismatoids.

The top line is straight and almost on a parallel plane with the cranial roof.

But then the only electrode shape that works right is two parallel planes.

Eight feet above this there is a parallel plane of acoustical tile.

Most levels consist of several parallel planes that the player character can move between.