That word is geocentric.
The median is the medical or anatomic term for the center of the body.
Its simply called the "center point" or "center". There is no fancy term for it.
core
Pitch
Medial means situated in the center.
concentric
"nucleus"
"nucleus"
The term for moving from one key center to another within a composition is called modulation.
Earth's core
Focal point
The term for the center of the universe is often referred to as the "cosmic center" or the "geocentric model" in ancient astronomy. However, in modern cosmology, there is no single defined center of the universe as space is expanding uniformly in all directions from the Big Bang.