Orientation and Directional Terms

Superior definition

toward the head end or upper part of a structure or the body; above

Superior example

the head is superior to the abdomen

Inferior definition

away from the head end or toward the lower part of a structure or the body; below

Inferior example

the naval is inferior to the chin

Anterior definition

toward or at the front of the body; in front of

Anterior example

the breastbone is anterior to the spine

Posterior definition

toward or at the back or the body; behind

Medial definition

toward or at the midline of the body; on the inner side of

Medial example

the heart is medial to the arm

Lateral definition

away from the midline of the body; on the outer side of

Lateral example

the arms are lateral to the chest

Intermediate definition

between a more medial and a more lateral structure

Intermediate example

the collarbone is intermediate between the breastbone and shoulder

Proximal definition

closer to the origin of the body part of the point of attachment of a limb to the body trunk

Proximal example

the elbow is proximal to the wrist

Distal definition

farther from the origin of a body part or the point of attachment of a limb to the body trunk

Distal example

the knee is distal to the thigh

Superficial definition

toward or at the body surface

Superficial example

the skin is superficial to the skeletal muscles

Deep definition

away from the body surface; more internal

Deep example

the lungs are deep to the skin