unfailing

adjective

un·​fail·​ing ˌən-ˈfā-liŋ How to pronounce unfailing (audio)
Synonyms of unfailingnext
: not failing or liable to fail:
a
: constant, unflagging
unfailing support/loyalty
known for her unfailing courtesy/optimism
b
: everlasting, inexhaustible
a subject of unfailing interest
c
: infallible, sure
an unfailing test
unfailingly
ˌən-ˈfā-liŋ-lē How to pronounce unfailing (audio)
adverb

Synonyms of unfailing

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Examples of unfailing in a Sentence

She is known for her unfailing optimism. an unfailing judge of personal character
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The young monarch is thought to have spent an hour alone before taking up her duties with the unfailing stoicism that would come to define her historic reign. — Hope Coke, Vanity Fair, 7 Feb. 2026 What is most important, always, is an unfailing loyalty to Trump. — Constance Grady, Vox, 25 Apr. 2025 One unfailing test of a country’s civilization, Winston Churchill once stated, lies in the mood of the public toward the treatment of crime and criminals. — The Christian Science Monitor, Christian Science Monitor, 25 Apr. 2025 In a world where trust now comes at a premium, trust in your GenAI strategy starts with trusting the data that fuels it, and the most unfailing data in your business lives in your contracts. — Monish Darda, Forbes.com, 8 Sep. 2025 See All Example Sentences for unfailing

Word History

First Known Use

14th century, in the meaning defined above

Time Traveler
The first known use of unfailing was in the 14th century

Rhymes for unfailing

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Browse Nearby Words

unfading
unfailing
unfailingly
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Cite this Entry

“Unfailing.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unfailing. Accessed 7 Jul. 2026.

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Kids Definition

unfailing

adjective
un·​fail·​ing ˌən-ˈfā-liŋ How to pronounce unfailing (audio)
ˈən-
1
: not likely to fail : constant, unflagging
unfailing support
2
: not likely to run out or be used up : everlasting, inexhaustible
an unfailing supply
3
: infallible sense 2
the unfailing mark of an amateur
unfailingly adverb

More from Merriam-Webster on unfailing

Nglish: Translation of unfailing for Spanish Speakers

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