medulla

A soft structure, especially the central part. Generally used in reference to the medulla oblongata, but may be used in reference to: 1) adrenal medulla 2) renal medulla 3) thymic medulla 4) medullary cavity of bone (bone marrow)

Specific

adrenal medulla medulla oblongata renal medulla

References

Stedman's Medical Dictionary 27th ed, Williams & Wilkins, Baltimore, 1999