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accuracy

/ˈækjərəsi//ˈækjərəsi/·noun
closeness to the true value — freedom from error
Fig. 1 — Five darts, one board, and the only thing that matters is where the truth is: the bullseye.
01Definition

Accuracy is closeness to the truth: a measurement, statement, or shot is accurate when it lands near the true value, whatever anyone else's attempts did. The anchor matters — accuracy is judged against reality, not against effort or consistency, which is why you can be careful and still inaccurate. From Latin accuratus, 'done with care', via cura, 'care' — the same root as curate. To verify a figure is to test its accuracy against the source; to calibrate an instrument is to buy accuracy back when it has drifted.

02In use
  • iHistorians praised the film's accuracy down to the buttons on the uniforms.
  • iiThe forecast's accuracy drops sharply beyond about ten days.
  • iiiCheck the translation's accuracy against the original before you quote it.
03Collocations
  • with pinpoint accuracy
  • improve accuracy
  • the accuracy of the data
  • a high degree of accuracy
  • check the accuracy of

Family accurate (adjective) · accurately (adverb) · inaccuracy (noun)

04Relations

=correctness, exactness, precision, fidelity, truth

≠inaccuracy, error

06TOEFL & IELTS

IELTS grades you on this word by name: 'Grammatical Range and Accuracy' is one of the four writing and speaking criteria, where accuracy means error-free control rather than ambition. In your own prose, 'the accuracy of the data' and 'a high degree of accuracy' are the working collocations, and 'with pinpoint accuracy' the idiomatic flourish. Keep the concept anchored to truth: accuracy is nearness to the correct value — its sibling precision measures consistency instead, a distinction science passages test.

07Asked
What is the difference between accuracy and precision?
Accuracy is closeness to the true value; precision is closeness of results to each other. Darts on the bullseye are accurate; darts in a tight knot off-centre are precise. In everyday speech the two overlap loosely as synonyms; science and measurement keep them strictly apart, and a good instrument needs both.
What does accuracy actually mean?
Freedom from error — conformity to truth or to a true value. The anchor is the point: accuracy is not carefulness, effort, or confidence, but nearness to how things actually are, which is why it can only be judged against a standard — the true weight, the original text, the historical record. In the scene above, the standard is painted on the board: the bull is the truth, and accuracy is measured from it.
Is 'accurateness' a word — accuracy or accurateness?
Both exist; accuracy is the standard choice. Accurateness has been in the language since the early 1600s and dictionaries still record it, but it is now rare enough to read as a mistake. The working family is: accurate (adjective), accurately (adverb), accuracy (noun), inaccuracy for the failure. If you find yourself writing accurateness, swap it — no meaning is lost.
Can something be precise but not accurate?
Easily — and it is the most instructive failure in measurement. A kitchen scale that returns 512 grams on every one of five weighings of a true 500-gram bag is admirably consistent and wrong every time. Consistency like that usually signals a systematic error — a fixed bias pulling every attempt the same way — which, once identified, can be corrected, restoring accuracy at a stroke.
What does accuracy mean for a model or a test score?
The proportion of answers it gets right: a model with 95% accuracy classifies 95 of every 100 cases correctly. The sense is the core meaning made countable — each prediction is compared with the truth, and accuracy reports the share that matched. It is a headline number worth reading carefully: on lopsided data, always guessing the majority can score high accuracy while learning nothing.
Which verbs and phrases go with accuracy?
You improve, ensure, check, question, or confirm accuracy; things are done with accuracy — 'with pinpoint accuracy', 'with deadly accuracy' for aim. Formal writing likes 'a high degree of accuracy', and 'the accuracy of' attaches the word to data, figures, reports, and translations. As a rough register guide, accuracy of information, precision of instruments — the collocations mirror the concepts.