Dictionary

aphonia Inability to speak.

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.

aplasia Failure to develop. See also atrophy.

aplasia of the breast See amastia.

apnea The absence of breathing (respiration).

apophysitis calcaneus Inflammation of the growth plate of the calcaneus, the bone at the back of the heel, where the Achilles tendon attaches. Apophysitis calcaneus occurs mainly in older children and adolescents, especially active boys. It can be very painful, although it may be dismissed as “growing pains.” Treatment includes activity limitation, medication, shoe inserts,…

apoptosis A form of cell death in which a programmed sequence of events leads to the elimination of cells without releasing harmful substances into the surrounding area. Apoptosis plays a crucial role in developing and maintaining the health of the body by eliminating old cells, unnecessary cells, and unhealthy cells. The human body replaces perhaps…

appendectomy Surgical removal of the appendix. An appendectomy is performed because of probable appendicitis. See also appendicitis.

appendicitis Inflammation of the appendix, usually associated with infection of the appendix. Appendicitis often causes fever, loss of appetite, and pain. Appendicitis may be suspected because of the medical history and physical examination. The pain of appendicitis can be located in various areas of the belly. If the appendix ruptures and infection spreads throughout the…

appendix A small outpouching from the beginning of the large intestine.

appendix epididymis A small cystic projection from the surface of the epididymis (a structure within the scrotum that is attached to the backside of the testis), which represents a remnant of the embryologic mesonephros.

appendix epiploica A finger-like projection of fat attached to the colon.