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

“No union is more profound than marriage, for it embodies the highest ideals of love, fidelity, devotion, sacrifice, and family,” he wrote.

From Los Angeles Times ● Jul. 26, 2026

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

"Gamers are willing to trade a little fidelity for convenience, but not to pay premium prices for something they don't own which stutters when the Wi-Fi dips," he said.

From BBC ● Jul. 23, 2026

McPeake noted that Quantinuum “has set the industry benchmarks in quantum compute,” referring to its Helios platform achieving an industry-leading 99.92% two-qubit gate fidelity.

From Barron's ● Jun. 29, 2026

Her hairdresser could count on absolute fidelity and punctuality.

From "I Know Why the Caged Bird Sings" by Maya Angelou

"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

These gate fidelities are well above the threshold needed for certain common error correcting codes, and should enable error detection in larger-scale systems.

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

Related Words

• devotion
• loyalty