fidelity

American  

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

noun

plural

fidelities

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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Related Words

See loyalty.

Other Word Forms

• nonfidelity noun
• unfidelity noun

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

In the West Bengal election, fish has slipped from the plate into the centre of the campaign, recast as proof of cultural fidelity and a rebuttal to charges of intrusion.

From BBC • Apr. 20, 2026

Rigetti plans to enhance its Cepheus system to achieve a median 99.5% two-qubit gate fidelity later this year.

From Barron's • Apr. 8, 2026

The mathematics are proprietary, but Hassibi said the effect was much like compressing a digital photograph without losing visual fidelity.

From The Wall Street Journal • Mar. 31, 2026

Her take is a maelstrom of splendid beauty and doomed love, colliding at a feverish pace that makes the fidelity to Brontë’s book moot.

From Salon • Feb. 23, 2026

Her hairdresser could count on absolute fidelity and punctuality.

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

Related Words

• devotion
• loyalty