Abdominal guarding: Tensing of the abdominal wall muscles to guard inflamed organs within the abdomen from the pain of pressure upon them. Abdominal guarding is detected when the abdomen is pressed and is an indication that inflammation of the inner abdominal (peritoneal) surface may be present due, for example, to appendicitis or diverticulitis. The tensed muscles of the abdominal wall automatically go into spasm to keep the tender underlying tissues from being irritated.
Aberration: (1) A deviation or irregularity. For example, a chromosome aberration is a deviation from the normal chromosome number or the normal chromosome structure. In this sense, aberration is also synonymous with deflection, departure, divergence, diversion, turning. (2) A mental aberration is a significant deviation from normal mental activity. In this sense, aberration is synonymous […]
- Abdominal muscles
Abdominal muscles: A large group of muscles in the front of the abdomen that assists in the regular breathing movement and supports the muscles of the spine while lifting and keeping abdominal organs such as the intestines in place. Abdominal muscles play a key role in exercises such as “sit-ups.” They are informally called the […]
Abiotic: 1. Not associated with living organisms. 2. Anything in the environment incapable of life, such as the soil or weather. 3. Incompatible with life or antagonist to it. Also called abiological.
- Abducent nerve
Abducent nerve: The sixth cranial nerve, which emerges from the skull to operate the lateral rectus muscle. This muscle draws the eye toward the side of the head. Paralysis of the abducent nerve causes inward turning of the eye.
Ablation: Removal or excision. Ablation is usually carried out surgically. For example, surgical removal of the thyroid gland (a total thyroidectomy) is ablation of the thyroid.