from
The Collaborative International Dictionary of English v.0.48
Medullary \Med"ul*la*ry\, a. [L. medullaris, fr. medulla marrow:
cf. F. m['e]dullaire.]
1. (Anat.)
(a) Pertaining to, consisting of, or resembling, marrow or
medulla.
(b) Pertaining to the medula oblongata.
[1913 Webster]
2. (Bot.) Filled with spongy pith; pithy.
[1913 Webster]
{Medullary groove} (Anat.), a groove, in the epiblast of the
vertebrate blastoderm, the edges of which unite, making a
tube (the medullary canal) from which the brain and spinal
cord are developed.
{Medullary rays} (Bot.), the rays of cellular tissue seen in
a transverse section of exogenous wood, which pass from
the pith to the bark.
{Medullary sheath} (Anat.), the layer of white semifluid
substance (myelin), between the primitive sheath and axis
cylinder of a medullated nerve fiber.
[1913 Webster]