n. 1. Physical or mental weariness resulting from effort or activity. 2. Something, such as tiring effort or activity, that causes tiredness or weariness: the fatigue of a long hike. 3. Physiology The decreased capacity or complete inability of an organism, organ, or part to function normally because of excessive stimulation or prolonged exertion. 4.
blood - the fluid (red in vertebrates) that is pumped through the body by the heart and contains plasma, blood cells, and platelets; blood carries oxygen and nutrients to the tissues and carries away waste products; the ancients believed that blood was the seat of the emotions
: a test of the blood; specifically : a laboratory test in which a sample of blood is withdrawn from the body to analyze the level of substances or cells (as glucose, hemoglobin, or white blood cells) that indicate the presence or probable development of a particular disease or medical condition (as diabetes, cardiovascular disease, or cancer) or ...