Patients may hear their physician use a variety of unfamiliar terms to describe body positions or motions.  This page is presented to describe some of the basic terms that may be used.

Cardinal Planes

Frontal Plane describes the plane dividing the front of the body and the back of the body.  This plane is pictured below in green.
Sagittal Plane describes the plane dividing the left hand and right hand portions of the body.  This plane is pictured below in pink.  
Transverse Plane describes the plane dividing the top portion and bottom portion of the body.  This plane is pictured below in purple.  

Directions

Medial describes the location of something closer to the midline of the body.  For example, the big toe is medial to the little toe.  
Lateral describes the location of something further from the midline of the body.  For example, the little toe is lateral to the big toe.  
Dorsal means the top of the foot. 
Plantar means the bottom of the foot--the sole.  
Anterior means the front of the body.  For example, your shin bone is anterior to your Achilles Tendon.  
Posterior means the back of the body.  For example, your heel bone lies posterior to your toes.    
Superficial means closer to the skin--less deep.
Deep, the opposite of superficial, means further into the body.  

Motions

Adduction describes the motion of bringing something towards the midline of the body.  For example, if the big toe were oriented so it was pointing away from the second toe and towards the opposite foot, it would be adducted.  
Abduction describes the motion of taking something away from the midline of the body.  For example, if the big little toe were oriented so it was pointing away from the other toes, it would be abducted.  

Dorsiflexion describes the motion of the foot where the toes or ball of the foot are lifted off the ground.  (See illustration below.)
Plantarflexion describes the motion of the foot where the toes or ball of the foot is pushed down towards the ground.  (See illustration below.) 

Inversion describes the motion of the foot where the foot is rolling over towards the medial, or inside portion, of the foot.  (See illustration below.) 
Eversion describes the motion of the foot where the foot is rolling over towards the lateral, or outside portion, of the foot.  (See illustration below.)

Pronation is a complicated motion involving all three cardinal planes.  Pronation involves movement of the arch in a plantarflexed, adducted and everted position. 
Supination is the opposite of pronation.  Supination involves movement of the arch in a dorsiflexed, abducted and inverted position. 

Positions

Varus describes the position of the foot when it is inverted. 
Valgus describes the position of the foot when it is everted. 
Cavus describes a high-arched structural position of the foot (commonly associated with a supinated foot, described above. 
Planus describes a low-arched structural position of the foot, (commonly associated with a pronated foot, described above.