noun fi·del·i·ty \ fə-ˈde-lə-tē , fī- \
|Updated on: 11 Aug 2018

Definition of fidelity

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)

fidelity was our Word of the Day on 06/30/2017. Hear the podcast!

Examples of fidelity in a Sentence

  1. 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 ShapiroNew York Times Book Review12 Dec. 2004
  2. 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 SendakCaldecott & Co.1988
  3. Chaucer's patient Griselda proved her fidelity to her husband by resisting the prodigious reasons he gave her for being unfaithful. —B. F. SkinnerBeyond Freedom and Dignity1971
  4. music with much higher fidelity than on cassettes

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

Recent Examples of fidelity from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fidelity.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Have a Little Faith in fidelity

You can have faith in "fidelity," which has existed in English since the 15th century; its etymological path winds back through Middle English and Middle French, eventually arriving at the Latin verb fidere, meaning "to trust." "Fidere" is also an ancestor of other English words associated with trust or faith, such as "fiduciary" (which means "of, relating to, or involving a confidence or trust" and is often used in the context of a monetary trust) and "confide" (meaning "to trust" or "to show trust by imparting secrets"). 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.

Origin and Etymology of fidelity

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

Synonym Discussion of 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

Other Audio Recording Terms

FIDELITY Defined for English Language Learners


Definition of fidelity for English Language Learners

  • : the quality of being faithful to your husband, wife, or sexual partner

  • : the quality of being faithful or loyal to a country, organization, etc.

  • : the degree to which something matches or copies something else

FIDELITY Defined for Kids


noun fi·del·i·ty \ fə-ˈde-lə-tē , fī- \

Definition of fidelity for Students

1 : loyalty
  • They swore fidelity to the king.
2 : accuracy
  • I described the scene with fidelity.

Word Root of fidelity

The Latin word fidēs, meaning “faith,” gives us the root fid. Words from the Latin fidēs have something to with being faithful. Fidelity is faith or loyalty. To confide in someone is to show trust in the person by telling her or him a secret. Someone who is confident has faith that he or she will do something correctly and successfully.

Law Dictionary


noun fi·del·i·ty \ fə-ˈde-lə-tē, fī- \

legal Definition of fidelity

: 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

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