fidelity

American  

[fi-del-i-tee, fahy-] / fɪˈdɛl ɪ ti, faɪ- /

noun

• fidelities
  plural

1. strict observance of promises, duties, etc..

   a servant's fidelity.

2. loyalty.

   fidelity to one's country.

   Antonyms:

   disloyalty

3. conjugal faithfulness.

4. adherence to fact or detail.

5. accuracy; exactness.

   The speech was transcribed with great fidelity.

   Synonyms:

   rigor, faithfulness, precision

6. Audio, Video. the degree of accuracy with which sound or images are recorded or reproduced.

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fidelity British  

/ fɪˈdɛlɪtɪ /

noun

1. devotion to duties, obligations, etc; faithfulness

2. loyalty or devotion, as to a person or cause

3. faithfulness to one's spouse, lover, etc

4. adherence to truth; accuracy in reporting detail

5. electronics the degree to which the output of a system, such as an amplifier or radio, accurately reproduces the characteristics of the input signal See also high fidelity

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Synonym Usage

See loyalty.

Other Word Forms

Derived Forms

• nonfidelity
  noun
• unfidelity
  noun

Inflected Forms

Nouns

• fidelities
  plural

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Etymology

Origin of fidelity

First recorded in 1500–10; late Middle English fidelite (from Middle French ), from Latin fidēlitās, equivalent to fidēli- (stem of fidēlis “loyal,” equivalent to fidē(s) faith + -lis adjective suffix) + -tās -ty ²

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Explanation

Fidelity is the quality of being faithful or loyal. Dogs are famous for their fidelity. Fidelity comes from the Latin root fides, which means faith, so fidelity is the state of being faithful. Marital fidelity is faithfulness to your spouse. If you're a journalist, your reports should have fidelity to the facts. Someone without fidelity to a religion or group belief is called an infidel.

Example Sentences

See Examples For:

fidelity fidelities

There’s no doubt that measuring mechanical functionality and discerning historical fidelity have become critical components of the conversation.

From Slate ● Sep. 16, 2026

While mothering her two teenagers, one of them newly identifies as nonbinary — “It was Laurel’s job to not make a big deal about this” — she obsesses about her husband’s questionable fidelity.

From Los Angeles Times ● Sep. 8, 2026

"This experiment develops techniques to better characterize the fidelity of hard quantum states under noise, increasing confidence that the quantum computer is solving a computationally hard problem."

From Science Daily ● Aug. 30, 2026

The impressive visual fidelity has been attributed to the amount of time Rockstar has spent working on the game, and its budget, which is thought to be among the most expensive in video game history.

From BBC ● Aug. 27, 2026

Then I should have asked you to accept my pledge of fidelity and to give me yours.

From "Jane Eyre" by Charlotte Brontë

Gates with the highest possible fidelities are essential because quantum errors accumulate exponentially.

From Science Daily ● Sep. 25, 2023

Furthermore, pushing the fidelities far beyond this threshold reduces the overhead needed to implement error correcting codes.

From Science Daily ● Sep. 25, 2023

In laboratory experiments, trapped ions have reached fidelities as high as 99.99%, according to a spokesperson for the company.

From Scientific American ● Feb. 13, 2023

Shallow quantum circuits need higher gate fidelities and more stability to limit decoherence.

From Nature ● Mar. 2, 2017

OD prepares us for the greater crusades by more commonplace fidelities.

From My Daily Meditation for the Circling Year by John Henry Jowett

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Related Words

• devotion
• loyalty

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