1. The passage of the branches of arteries or nerves to the tissues and organs. 2. The area in which the branches of an artery or a nerve terminate, or the area supplied by such an artery or nerve. 3. The relative numbers of people in each of various categories or populations such as in different age, gender, or occupational samples. 4. Partition. 5. The pattern of occurrence of a substance within or between organelles, cells, tissues, organisms, or taxa.