from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun Faithfulness to obligations, duties, or observances.
  • noun The condition or behavior of engaging in sex only with one's spouse or only with one's partner in a sexual relationship.
  • noun Exact correspondence with fact or with a given quality, condition, or event; accuracy.
  • noun The degree to which an electronic system accurately reproduces the sound or image of its input signal.

from The Century Dictionary.

  • noun Good faith; careful and exact observance of duty or performance of obligations: as, conjugal or official fidelity.
  • noun Faithful devotion or submission; unswerving adherence; close or exact conformity; fealty; allegiance: as, fidelity to a husband or wife, or to a trust; fidelity to one's principles or to instructions; the dog is the type of fidelity.
  • noun Faithful adherence to truth or reality; strict conformity to fact; truthfulness; exactness; accuracy: as, the fidelity of a witness, of a narrative, or of a picture.
  • noun An order of Portugal, founded by John VI. in 1823 for the supporters of the monarchy during the insurrectionary movements in that country. Synonyms Faith, integrity, trustiness, trustworthiness, conscientiousness; Constancy, Faithfulness, etc. (see firmness).

from the GNU version of the Collaborative International Dictionary of English.

  • noun Adherence to a person or party to which one is bound; loyalty.
  • noun Adherence to the marriage contract.
  • noun Adherence to truth; veracity; honesty.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun Faithfulness to one's duties.
  • noun Loyalty to one's spouse or partner, including abstention from extramarital affairs (except in an open marriage).
  • noun Accuracy, or exact correspondence to some given quality or fact.
  • noun The degree to which a system accurately reproduces an input.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun accuracy with which an electronic system reproduces the sound or image of its input signal
  • noun the quality of being faithful


from The American Heritage® Dictionary of the English Language, 4th Edition

[Middle English fidelite, from Old French, from Latin fidēlitās, from fidēlis, faithful, from fidēs, faith; see bheidh- in Indo-European roots.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

15th century, from French fidélité from Latin fidēlitās, from fidēlis ("faithful"), from fidēs ("faith, loyalty") (English faith), from Proto-Indo-European *bʰidʰ-, zero-grade of Proto-Indo-European *bʰeydʰ- (“to command, to persuade, to trust”) (English bide).


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  • The H.M.S. Fidelity was listed as a "transport" captured at Yorktown in 1781.

    October 29, 2007

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    November 13, 2008