Supine: This refers to having the back or dorsal surface downward. A person who is in a supine position is lying face up as opposed to prone. For a more complete listing of terms used in medicine for spatial orientation, please see the entry to "Anatomic Orientation Terms". SLIDESHOW Sex-Drive Killers: The Causes of Low Libido See Slideshow From Healthy Resources 11 Ways to Treat Your Psoriasis NaturallyFood Dos and Don’ts to Tame InflammationHere’s What Head Lice Actually Look Like Featured Centers What Are the Best PsA Treatments for You?Understanding Biologics 10 Things People With Depression Wish You Knew Health Solutions From Our Sponsors Shot-Free MS Treatment Your Child and COVID-19 References Jameson, J. Larry, et al. Harrison's Principles of Internal Medicine, 20th Ed. New York: McGraw-Hill Education, 2018.