Subdivision is a term used to describe the act of breaking something down into smaller parts. COMPARTMENT, DEPARTMENT, DIVISION, PART, UNIT, BRANCH, SECTION, ARM, and SECTOR are all words that can be used to refer to a subdivision. Each word has a slightly different meaning, but they all refer to the same concept of breaking something down into smaller parts. For example, a COMPARTMENT is a distinct area within a larger space, while a DEPARTMENT is a distinct area within an organization. A DIVISION is a large PART of something that is divided into smaller parts, while a PART is a small portion of something. A UNIT is a single thing or group of things that make up a larger whole, while a BRANCH is a PART of something that extends from the main PART. A SECTION is a distinct PART of something, while an ARM is a PART of something that extends from the main PART. Finally, a SECTOR is a distinct area within a larger space.