Requirement for quality: Expression of the needs or their translation into a set of quantitatively or qualitatively stated requirements for the characteristics of an entity to enable its realization and examination.

Radiation: A method of transmission of energy.

Range: (1) Extent of coverage of effectiveness. (2) Measure of distance.

Ratio Bridge: A bridge circuit that uses a calibrated resistive or calibrated inductive voltage divider for one side of the bride.

Reference Line: A line from which all other measurements are taken.

Reference Plane: A reference lie that has been rotated through 360 degrees.

Repeatability: Same reading each time for the same solution.

Resonance: An excited state of a stable particle causing a sharp maximum in the probability of absorption of electromagnetic radiation.

Restoring Force: The constant mechanical force provided.

RHO: The magnitude of the reflection coefficient.

Scale: (1) Something graduated when used as a measure or rule. A series of spaces marked by lines to indicate the magnitude of some quantity. (2) A weighing device.

Scintillation Counter: A device used for the detection of radioactivity.

Secondary Emission: Electron emission that is the direct result of the impact of electrons against a surface.

Seeback Effect: The EMF produced in a circuit containing two contacting conductors of different metals having two junctions at different temperatures.

Sensitivity: Full scale output divided by the rated capacity of a given transducer / load cell.

Sensor: Element of measuring instrument or measuring chain that is directly or indirectly affected by the measurand.

Servo System: A electromechanical system which is used for positioning one element of a system in relation to another.

Shear: A deformation of an object in which parallel planes remain parallel but are shifted in a direction parallel to themselves.

Solenoid Valve: A valve actuated by a solenoid for controlling the flow of gases or liquid in pipes.

Span: Modules of the difference between the two limits of a normal range.

Solid: The state in which a substance has no tendency to flow under moderate stress.

Specifications: The range of values or numerical value which ties the performance of the product parameter.

Spectrum: (1) The entire range of wavelengths within which electromagnetic radiations occur. (2) A segment of wavelengths which has a special function or possesses special properties.

Stability: The ability of a measuring instrument to maintain constant metrological characteristics with time.

Standard: (1) Conforming to or constituting a standard of measurement or value. (2) a basis for comparison. (3) the ideal in terms of which something can be judged.

Standard Deviation: A mathematical quantity used to characterize the dispersion of results.

Standard Operating Conditionsstandard temperature and pressure (STP): Defined temperature and pressure to which all values are referenced for comparison.

Standard Pressure: The pressure exerted by a column of mercury exactly 760 mm high.

Standard Uncertainty: Uncertainty of the result of a measurement expressed as a standard deviation.

Strain: Deformation of a material body under the action of applied forces.

Straightness: The uniformity of direction throughout the extent of that feature.

Stress: Force that produces strain on a physical body.

Stroboscope: Scientific instrument that provides a flashing light synchronized with the periodic movement of an object.

Subcontractor: Organization that provides a product to the supplier.

Supplier: Organization that provides a product to a customer.

Surface Tension: The tendency of the surface of a liquid to contract.

Tachometer: An instrument for measuring rotational speed in revolutions per minute.

Temperature Coefficient: The change in measured value per unit change in temperature.

Temperature Compensation: The method of reducing the effect of a change in temperature on a force measuring instrument.

Terminal Linearity: Ratio of the actual error voltage in the output to the total input voltage.

Termination: The load connected to the output end of a circuit or transmission line.

Testing: A means of determining the capability of an item to meet specified requirements by subjecting the item to a set of physical, chemical, environmental or operation actions and conditions.

Test Instrument: The device being compared with the calibration standard.

Test Line Limit: The pass or fail limit.

Theodolite: A optical instrument used for measuring horizontal or vertical angles.

Thermistor: A semiconductor device made of materials whose resistance varies as a function of temperature.

Tilt Graticule: A graduate reticule used in Collimators for measuring vertical and horizontal tilt, or angular deviation.

Time: Measurement of duration.

Torque: Cause of rotary motion. It is equal to the applied force multiplied by the distance from the center of rotation.

Torr: 1/760 of and atmosphere.

Total quality management: Management approach of an organization, centered on quality based on the participation of its member and aiming at long-term success through customer satisfaction and benefits of all members of the organization and to society.

Traceability: Ability to trace the history, application, or location of an entity by means of recorded identification.

Transducer: A device that provides an output quantity having a determined relationship to the force.

Transfer: Standard used as in intermediary to compare standards.

True Mass: Mass as measured in a vacuum.

Uncertainty: A parameter, associated with the result of a measurement that characterizes the dispersion of the values that could reasonably be attributed to the measured.

Unit: A value, quantity, or magnitude of which other values, quantities, or magnitudes are expressed.

Vacuum: Any pressure below atmospheric.

Velocity Constant: The time rate of change of position.

Velocity Constant: The ratio of the velocity of propagation in a transmission line to the velocity of light.

Verification: Confirmation by examination and provision of objective evidence that specified requirements have been filled.

Vibration: Mechanical oscillations or motion about a reference point or equilibrium.

Viscosity: Resistance of a liquid to sheer forces (and hence to flow).

VSLI: Very Large Scale Integration.

Volatile: Readily vaporizable at a relatively low temperature.

Volume: The amount of space which matter occupies.

Wave Front: A surface composed at any instant of all the points just reached by a vibration disturbance in its propagation through a medium.

Weight: The force of gravity acting on an object.