This glossary of medical terms is a list of definitions about medicine, its sub-disciplines, and related fields.
Aarskog–Scott syndrome – (AAS) A rare, inherited (X-linked) disease characterized by short stature, facial abnormalities, skeletal and genital anomalies.
Abdomen – The part of the body between the chest and pelvis, which contains most of the tubelike organs of the digestive tract, as well as several solid organs.
Abdominal external oblique muscle – The largest, and outermost, of the three flat muscles of the lateral anterior abdominal wall.
Abdominal internal oblique muscle – A muscle of the abdominal wall, which lies below the external oblique and just above the transverse abdominal muscles.
Abductor pollicis brevis muscle – A muscle in the hand that abducts (straightens) the thumb.
Abductor pollicis longus muscle – One of the extrinsic muscles of the hand. Its major function is to abduct the thumb at the wrist.
Abscess – A collection of pus that has built up within the tissue of the body.
Accommodation – the process by which the eye focuses on an object.
Accommodation reflex – a reflex action of the eye, measured as a response to focusing on a near object, then looking at a distant object (and vice versa).
Acetabulum – a concave surface of the pelvis, which forms the pelvic section of the hip joint.
Achilles tendon – a tendon of the back of the leg, and the thickest in the human body. It attaches the plantaris, gastrocnemius (calf) and soleus muscles to the calcaneus (heel) bone.
Acne – a long-term skin disease that occurs when hair follicles are clogged with dead skin cells and oil from the skin.
Acne vulgaris – see Acne
Acupressure – an alternative medicine technique where pressure is applied to acupuncture points. Pressure may be applied by hand, by elbow, or with various devices.
Acupuncture – a form of alternative medicine in which thin needles are inserted into the body.
Adam's apple – the lump or protrusion that is formed by the angle of the thyroid cartilage surrounding the larynx seen especially in males.