(Botany) an association of a fungus and a plant in which the fungus lives within or on the outside of the plant's roots forming a symbiotic or parasitic relationship. See ectotrophic mycorrhiza, endotrophic mycorrhiza. [C19: from myco- + Greek rhiza root]
Medical Definition of POSTERIOR MEDIAN SULCUS. : a shallow groove along the midline of the posterior part of the spinal cord that separates the two posterior funiculi and is the external boundary of the posterior median septum. a shallow groove along the midline of the posterior part of the spinal cord that separates the two posterior funiculi and is the external boundary of the posterior median septum.
The nose is on the anterior side of the head. Posterior: Toward the rear. The posterior side of the head is frequently covered in hair. Dorsal: In humans, toward the back of the torso.The shoulder blades are dorsal to the ribs. Ventral: In humans, toward the front of the torso. The navel is on the ventral aspect of the body. In humans, dorsal and ventral are mostly synonymous with posterior and anterior, and the latter terms are often used.entral: In humans, toward the front of the torso. The navel is on the ventral aspect of the body. In humans, dorsal and ventral are mostly synonymous with posterior and anterior, and the latter terms are often used.