Medullary ray

Definition

A renal, cortical lobule, consisting of the ascending or descending limbs of the loop of Henle or of the collecting tubules; medullary rays are regions where parallel arrays of straight tubules travel perpendicular to the capsule and extend from the cortex to the medulla.

Also known as Ferrein's pyramid, kidney medullary ray, renal medullary ray — per UBERON

The Medullary ray is a part of the Urinary.