Umbilical plane

Umbilical plane
umbilicus

The umbilical plane is the transverse plane passing through the umbilicus.

This is similar to the location of the mid-transverse plane, which is the transverse plane made through the waist, into roughly two halves: the torso, arms and head on the top, and the pelvis and legs (including hands if arms are held vertically) at the bottom. That is the plane seen in the picture.