In physics and engineering, measurement is the activity of comparing physical quantities of real-world objects and events. Established standard objects and events are used as units, and the measurement results in a given number for the relationship between the item under study and the referenced unit of measurement. Measuring instruments are the means by which this translation is made. All measuring instruments are subject to varying degrees of instrument error.
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Noun 1. instrument that shows the extent or amount or quantity or degree of something (synonym) measuring system, measuring device (hypernym) instrument (hyponym) accelerometer