Anatomical Terminology

Directional Terms

Directional terms serve to describe position of structures relative to other structures: an organ described as rostral is closer to the head, whereas a caudal organ is closer in proximity to the feet.
Anatomical terms can be combined to more precisely describe the location of an organ or a region. For example, one might say that the right chest muscle, also called the pectoralis major, is anterolateral to the breastbone, also known as the sternum. This indicates that the right chest muscle is both anterior and lateral to the breast bone. But when relating the right shoulder to the right chest muscle, the appropriate directional term becomes superolateral because the shoulder is above, or superior to, and lateral to the right chest muscle. Directional terms are chosen based on the organs or regions being examined as they relate to each other.

Common Directional Terms

Term Meaning Example
anterior front, toward the front The breastbone is anterior; the spinal column is posterior.
posterior back, toward the back
distal farther from the point of origin The elbow is proximal to the shoulder; the wrist is distal to the shoulder.
proximal closer to the point of origin
dorsal the back surface Surgery on the spine requires a dorsal approach; surgery to remove an appendix requires a ventral approach.
ventral the front surface/belly
superior located above or over The heart is superior to the stomach; the intestines are inferior to the stomach.
inferior located below or underneath
lateral the side, moving away from the midline Lateral to the eye is the ear; medial to the eye is the nose.
medial moving toward the midline away from the side
cephalic (cranial) in relation to the head, toward the head A baby in the cephalic presentation is born head first; within the skull, the frontal lobe of the brain is rostral while the occipital lobe is caudal.
rostral in relation to the front end, toward the nasal/oral region
caudal in relation to the back or tail end
bilateral both sides Bilateral fractures are bone fractures on both sides of the body; a unilateral fracture is a broken bone that has occurred on one side only.
unilateral one side
ipsilateral on the same side The right elbow is ipsilateral to the right wrist but contralateral to the left elbow.
contralateral on opposite sides
parietal refers to body cavity wall The parietal pleura is the membrane lining the cavity where the lungs are located; the visceral pleura is the membrane lining the lungs.
visceral refers to organs within body cavity
axial relating to the central part of the body The axial skeleton consists of the head, neck, and trunk; the appendicular skeleton consists of the limbs (arms and legs).
appendicular relating to the limbs
superficial close to the surface A superficial wound injures the outer portion of the skin; a deep wound penetrates skin, fat, tissue, and muscle.
deep farther from the surface

Directional Terms in Human Anatomy

Directional terms describe the location of one body part relative to another. These terms are always named from the perspective of the person being examined, not the examiner. The right side is the person's right side, not the right side of the examiner.