Certain terms are used to describe the location of body parts, regions of the body, and imaginary planes by which the body can be sectioned. You should become familiar with these terms before your study of anatomy and physiology begins. Anatomical terms are useful only if everyone has in mind the same position of the body and is using the same reference points. Therefore, we will assume that the body is in the anatomical position: standing erect, with face forward, arms at the sides, and palms and toes directed forward, as illustrated in Figure 1.1.
Directional Terms
Directional terms are used to describe the location of one body part in relation to another (Fig. 1.2):
Anterior (ventral) means that a body part is located toward the front. The windpipe (trachea) is anterior to the esophagus.
Posterior (dorsal) means that a body part is located toward the back. The heart is posterior to the rib cage.
Superior means that a body part is located above another part, or toward the head. The face is superior to the neck.
Inferior means that a body part is below another part, or toward the feet. The navel is inferior to the chin.
Medial means that a body part is nearer than another part to an imaginary midline of the body. The bridge of the nose is medial to the eyes. toward the median plane.
Lateral means that a body part is farther away from the midline. toward the right or left.
Proximal means that a body part is closer to the point of attachment or closer to the trunk. The elbow is proximal to the hand.
Distal means that a body part is farther from the point of attachment or farther from the trunk or torso. The hand is distal to the elbow.
Superficial (external) means that a body part is located near the surface. The skin is superficial to the muscles.
Deep (internal) means that the body part is located away from the surface. The intestines are deep to the spine.
Central means that a body part is situated at the center of the body or an