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infallible

[in-fal-uh-buh l] /ɪnˈfæl ə bəl/
adjective
1.
absolutely trustworthy or sure:
an infallible rule.
2.
unfailing in effectiveness or operation; certain:
an infallible remedy.
3.
not fallible; exempt from liability to error, as persons, their judgment, or pronouncements:
an infallible principle.
4.
Roman Catholic Church. immune from fallacy or liability to error in expounding matters of faith or morals by virtue of the promise made by Christ to the Church.
noun
5.
an infallible person or thing.
Origin of infallible
late Middle English
1375-1425
First recorded in 1375-1425; late Middle English word from Medieval Latin word infallibilis. See in-3, fallible
Related forms
infallibility, infallibleness, noun
infallibly, adverb
noninfallible, adjective
noninfallibly, adverb
Synonyms
1, 2. See reliable.
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2017.
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Examples from the Web for infallible
Contemporary Examples
Historical Examples
  • Mrs. Turnbull's recipe, infallible for all aches, bruises, and strains.

  • She is not so infallible a markswoman, but that she might shoot at a crow and kill a pigeon.

    Maid Marian Thomas Love Peacock
  • Even the simplest of them—to do good to other people—is an instant and infallible specific.

    Pax Vobiscum Henry Drummond
  • How, you clever and infallible members of this present generation, do you judge her?

    Priestess of the Flame Sewell Peaslee Wright
  • This freshness, however, is not to be taken for an infallible sign of 7.

British Dictionary definitions for infallible

infallible

/ɪnˈfæləbəl/
adjective
1.
not fallible; not liable to error
2.
not liable to failure; certain; sure: an infallible cure
3.
completely dependable or trustworthy
noun
4.
a person or thing that is incapable of error or failure
Derived Forms
infallibility, infallibleness, noun
infallibly, adverb
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for infallible
adj.

early 15c., from Medieval Latin infallibilis, from in- "not, opposite of" (see in- (1)) + Late Latin fallibilis (see fallible). In reference to Popes, attested from 1870. Related: Infallibly.

Online Etymology Dictionary, © 2010 Douglas Harper
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