fidelity

noun

fi·​del·​i·​ty fə-ˈde-lə-tē 

fī-

plural fidelities

1

a

: the quality or state of being faithful

his fidelity to his wife

b

: accuracy in details : exactness

The movie's director insisted on total fidelity to the book.

2

: the degree to which an electronic device (such as a record player, radio, or television) accurately reproduces its effect (such as sound or picture)

Did you know?

Have a Little Faith in Fidelity

Fidelity came to English by way of French in the 15th century, and can ultimately be traced back to the Latin fidēlis, meaning "faithful, loyal, trustworthy." While fidelity was originally exclusively about loyalty, it has for centuries also been used to refer to accuracy, as in “questions about the fidelity of the translation.” Nowadays fidelity is often used in reference to recording and broadcast devices, conveying the idea that a broadcast or recording is "faithful" to the live sound or picture that it reproduces.

Synonyms

• adhesion
• allegiance
• attachment
• commitment
• constancy
• dedication
• devotedness
• devotion
• faith
• faithfulness
• fastness
• fealty
• loyalty
• piety
• steadfastness
• troth

Choose the Right Synonym for fidelity

fidelity, allegiance, fealty, loyalty, devotion, piety mean faithfulness to something to which one is bound by pledge or duty.

fidelity implies strict and continuing faithfulness to an obligation, trust, or duty.

marital fidelity

allegiance suggests an adherence like that of citizens to their country.

pledging allegiance

fealty implies a fidelity acknowledged by the individual and as compelling as a sworn vow.

fealty to the truth

loyalty implies a faithfulness that is steadfast in the face of any temptation to renounce, desert, or betray.

valued the loyalty of his friends

devotion stresses zeal and service amounting to self-dedication.

a painter's devotion to her art

piety stresses fidelity to obligations regarded as natural and fundamental.

filial piety

Examples of fidelity in a Sentence

Yet as Reardon emphasizes early on, fidelity to facts was never the point. The same dinner with friends could appear over and over in Fisher's published work, rejiggered each time to make a different point. —Laura Shapiro, New York Times Book Review, 12 Dec. 2004

It is a world familiar to all children, and it is this fidelity to child life that gives resonance to Hoffmann's tale and makes it an extraordinary work of art. —Maurice Sendak, Caldecott & Co., 1988

Chaucer's patient Griselda proved her fidelity to her husband by resisting the prodigious reasons he gave her for being unfaithful. —B. F. Skinner, Beyond Freedom and Dignity, 1971

music with much higher fidelity than on cassettes

they have never wavered in their fidelity to the cause of freedom

Recent Examples on the Web

Material features can also include things like colophons—formulas at the end of a text that attest to its completeness and fidelity and often also include the name of the copyist—doodles in the margins, mistakes and corrections, even handwriting style. —The Editors, JSTOR Daily, 22 Apr. 2025

Further testing will be performed at ESA’s Astronaut Centre in Cologne, Germany, which will have facilities to replicate the Moon’s surface with even greater fidelity. —James Morris, Forbes.com, 12 Apr. 2025

Liberal children tended to recall more accurately the ratio of desirable and undesirable traits in the characters of the story; their memories possessed greater fidelity to the story as it was originally told. —Matt Richtel, New York Times, 8 Apr. 2025

And those looking for fidelity should simply read the book — a great experience. —Jay Nordlinger, National Review, 7 Apr. 2025

Word History

Etymology

Middle English fidelite, borrowed from Middle French fidelité, borrowed from Latin fidēlitāt-, fidēlitās, from fidēlis "faithful, loyal, trustworthy" (from fidē-, stem of fidēs "trust, belief, faith" + -lis, denominal suffix of appurtenance) + -itāt-, -itās -ity — more at faith entry 1

First Known Use

15th century, in the meaning defined at sense 1a

Phrases Containing fidelity

• high fidelity

Rhymes for fidelity

• infidelity

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Kids Definition

fidelity

noun

fi·​del·​i·​ty fə-ˈdel-ət-ē 

fī-

plural fidelities

1

a

: the quality or state of being faithful

b

: exactness in details

2

: the degree to which an electronic device (as a record player, radio, or television) correctly reproduces its effect (as sound or a picture)

Legal Definition

fidelity

noun

fi·​del·​i·​ty fə-ˈde-lə-tē, fī- 

: the quality or state of being faithful or loyal

especially : loyalty to one's spouse in refraining from adultery and sometimes in submitting to a spouse's reasonable sexual desires