Dictionary

oligopeptide A molecule that is composed of a few amino acids linked to one another.

oligosaccharidosis One of a group of inherited metabolic disorders that are similar to the mucopolysaccharidoses. These conditions include aspartylglycosaminuria (AGU), fucosidosis, mannosidosis, and multiple sulfatase deficiency. Symptoms generally include deterioration of the nervous system. No treatment is available.

oligospermia Fewer sperm than usual. Azospermia, by contrast, means absolutely no sperm at all.

oliguria Less urination than normal.

Ollier’s disease See multiple enchondromatosis.

omega-3 fatty acids A class of fatty acids found in fish oils, especially salmon and other cold-water fish, that acts to lower the levels of total cholesterol and LDL cholesterol in the blood. Omega-3 fish oil is considered a neutraceutical, a food that provides health benefits. Eating fish has been reported to protect against age-related…

omentum A sheet of fat that is covered by peritoneum. The greater omentum is attached to the bottom edge of the stomach and hangs down in front of the intestines. Its other edge is attached to the transverse colon. The lesser omentum is attached to the top edge of the stomach and extends to the…

Ommaya reservoir A device that is implanted under the scalp to deliver anticancer drugs to the fluid surrounding the brain and spinal cord.

omphalo- Prefix indicating a relationship to the umbilicus (the navel). From the Greek word for the decorative boss protruding from the center of a Greek warrior’s shield.

omphalocele A birth defect in which part of the intestine, covered only by a thin transparent membrane, protrudes outside the abdomen at the umbilicus. An omphalocele occurs due to a failure during embryonic development for a section of the intestines (the midgut) to return from outside the abdomen and reenter the abdomen as it should….

omphalomesenteric duct A narrow tube that is present in the early embryo that connects the midgut of the embryo to the yolk sac outside the embryo through the umbilical opening. Later in development, it is usually obliterated, but a remnant of it may persist, most commonly as a finger-like protrusion from the small intestine that…

onchocerciasis See river blindness.