The act or process of dividing something into parts. The state of being so divided. Something that divides or separates, as a wall dividing one room or cubicle from another. A wall, septum, or other separating membrane in an organism. A part or section into which something has been divided. Division of a country into separate, autonomous nations. Mathematics An expression of a positive integer as a sum of positive integers. Mathematics The decomposition of a set into a family of disjoint sets. Computer Science A section of storage space on a hard disk. Law Division of property, especially real estate. To divide into parts, pieces, or sections. To divide or separate by means of a partition: We partitioned off the alcove to make another bedroom. To divide (a country) into separate, autonomous nations.