accuracy

n. preciseness, exactness

In the fields of science, engineering, industry and statistics, accuracy is the degree of conformity of a measured or calculated quantity to its actual (true) value. Accuracy is closely related to precision, also called reproducibility or repeatability, the degree to which further measurements or calculations show the same or similar results. The results of calculations or a measurement can be accurate but not precise; precise but not accurate; neither; or both. A result is called valid if it is both accurate and precise. The related terms in surveying are error (random variability in research) and bias (non-random or directed effects caused by a factor or factors unrelated by the independent variable).
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Noun
1. the quality of nearness to the truth or the true value; "he was beginning to doubt the accuracy of his compass"; "the lawyer questioned the truth of my account"
(synonym) truth
(antonym) inaccuracy
(hypernym) quality
(hyponym) exactness, exactitude
(attribute) accurate
2. (mathematics) the number of significant figures given in a number; "the atomic clock enabled scientists to measure time with much greater accuracy"
(hypernym) quality
(classification) mathematics, math, maths

(n.)
The state of being accurate; freedom from mistakes, this exemption arising from carefulness; exact conformity to truth, or to a rule or model; precision; exactness; nicety; correctness; as, the value of testimony depends on its accuracy.
  

The degree of conformity of a measured or calculated value to its actual or specified value. Contrast with precision.