Dictionary

aplasia of the breast See amastia.

aplasia Failure to develop. See also atrophy.

apical The adjective for apex, the tip of a pyramidal or rounded structure, such as the lung or the heart. For example, an apical lung tumor is a tumor located at the top of the lung.

aphonia Inability to speak.

apheresis The process of removing a specific component from blood temporarily. Also known as hemapheresis and pheresis. Forms of apheresis include plasmapheresis, harvesting plasma or liquid part of the blood; leukapheresis, harvesting leukocytes or white blood cells; granulocytapheresis, harvesting granulocytes; lymphocytapheresis, harvesting lymphocytes; lymphoplasmapheresis, harvesting lymphocytes and plasma; and plateletpheresis, harvesting platelets.

aphasia Literally, no speech. Aphasia may also be used to describe defects in spoken expression or comprehension of speech.

aphagia Inability to eat.

Apgar score An objective score of the condition of a baby after birth. This score is determined by scoring the heart rate, respiratory effort, muscle tone, skin color, and response to a catheter in the nostril. Each of these objective signs receives 0, 1, or 2 points. An Apgar score of 10 means an infant…

apex The Latin word for summit, the apex is the tip of a pyramidal or rounded structure, such as the lung or the heart. The apex of the lung is indeed its tip—its rounded most superior portion. The apex of the heart is likewise its tip, but it is formed by the left ventricle, so…

Apert syndrome The best-known type of acrocephalosyndactyly, a group of disorders characterized by malformations of the skull, face, hands, and feet. Apert syndrome is inherited as an autosomal dominant trait. See also acrocephalosyndactyly; fibroblast growth factor receptor.

aperient Laxative.

AP 1 Angina pectoris. 2 Arterial pressure. 3 In endocrinology, anterior pituitary gland. 4 In anatomy, anteroposterior.