Electronic Engineering Glossary Terms

Selected item. A selected item is an existing item, under the control of another design activity or defined by a nationally recognized standardization document, that is subjected to refined acceptance criteria (such as fit, tolerance, performance, or reliability) to meet design requirements.

Set. A unit or units and necessary assemblies, subassemblies and parts connected or associated together to perform an operational function. (Examples: radio receiving set; sound measuring set, which includes parts assemblies and units such as cable, microphone and measuring instruments; radar homing set) Set is also used to denote a collection of like parts such as a toolset or a set of tires.

Specification. A document prepared to support acquisition that describes essential technical requirements for materiel and the criteria for determining whether those requirements are met. (MIL-STD-961).

Standard. A document that establishes uniform engineering or technical criteria, methods, processes, and practices. (MIL-STD-962).

Standardization document. A document developed by the Government or private sector association, organization, or technical society which plans, develops, establishes or coordinates standards, specifications, handbooks, or similar documents for the purpose of standardizing items, materials, processes, or procedures.

Standard, company. A company document which establishes engineering and technical limitations and applications for items, materials, processes, methods, designs and engineering practices unique to that company. (MIL-DTL-31000).

Subassembly. Two or more parts which form a portion of an assembly or a unit replaceable as a whole, but having a part or parts which are individually replaceable. (Examples: gun mount stand, window sash, recoil mechanism, floating piston, telephone dial, Intermediate Frequency (IF) strip, terminal board with mounted parts.) (MIL-STD-280)

Supplier. See Vendor.

Symmetrically opposite parts. Symmetrically opposite parts are those parts which are mirror images of each other.

System (general). A composite of equipment, skills and techniques capable of performing or supporting an operational role or both. A complete system includes all equipment, related facilities, material, software, services and personnel required for its operation and support to the degree that it can be considered a self-sufficient unit in its intended operational environment. (MIL-STD-280)

Unit. An assembly or any combination of parts, subassemblies and assemblies mounted together normally capable of independent operation in a variety of situations. (Examples: Hydraulic jack, electric motor, electronic power supply, internal combustion engine, electric generator, radio receiver.)
NOTE: The size of an item is a consideration in some cases. An electric motor for a clock may be considered as a part because it is not normally subject to disassembly.

Vendor. A source from whom a purchased item is obtained; used synonymously in this standard with the term supplier.