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

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

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

One reason is that the annals of Congress are full of female successors who did exactly that, partly out of fidelity to their seats’ previous occupants.

From Slate ● Jul. 24, 2026

"Damon's Odysseus is stubborn, overconfident and sacrilegious, but doesn't bear that much resemblance to the conniving, hypocritical egotist of lore who fretted over his wife's fidelity," she noted.

From BBC ● Jul. 15, 2026

The one place they urged some fidelity to the past versions was in the score.

From Los Angeles Times ● Jun. 5, 2026

From a production standpoint, its fidelity is wide and deep.

From The Wall Street Journal ● May 25, 2026

Every time that cell divided, in the many embryological steps that went into making you, the original set of genetic instructions was duplicated with great fidelity.

From "Cosmos" by Carl Sagan

"Neutral atoms are the most scalable type of quantum computer, but they didn't have high-entanglement fidelities until now," says Shaw.

From Science Daily ● Oct. 11, 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

They will have to decide which qubits in the computer to use and how to deal with ranges of operational fidelities and low-level precisions that are foreign to most modern programmers.

From Nature ● Sep. 12, 2017

Of the day's task, of homely fidelities and services, of marriage and parenthood and neighborhood and citizenship, it made almost no account.

From The Negro and the Nation A History of American Slavery and Enfranchisement by Merriam, George Spring

Related Words

• devotion
• loyalty