1. A standard or unit for measuring. n/ 2. In building, a selected unit of measure, ranging in size from a few inches to several feet, used as a basis for planning and standardisation of building materials. n/ 3. In automatic data processing, a program unit that is discrete and identifiable with respect to compiling, combining with other units and unloading; e.g., the input from an assembler. n/ 4. An item, assembly, subassembly, board, card, or component which is designed as a single unit to facilitate and simplify production line techniques, transportation, supply, and maintenance processing