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Synonyms

unfailing

American  
[uhn-fey-ling] / ʌnˈfeɪ lɪŋ /

adjective

  1. not failing; fail; not giving way; not falling short of expectation; completely dependable.

    an unfailing friend.

  2. inexhaustible; endless.

    unfailing resources; unfailing good humor.
unfailing British  
/ ʌnˈfeɪlɪŋ /

adjective

  1. not failing; unflagging

  2. continuous or unceasing

  3. sure; certain

"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

Other Word Forms

  • unfailingly adverb
  • unfailingness noun

Etymology

Origin of unfailing

Middle English word dating back to 1350–1400; un- 1, failing

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“The Ten Year Affair” handles these twists with unfailing intelligence, capturing the sincere but confusingly improvised mores of marriage today.

From The Wall Street Journal • Oct. 31, 2025

It was clear he had a brilliant, creative mind, a kind spirit, and an unfailing belief in himself and his projects.

From Los Angeles Times • Jul. 25, 2025

A major contributor to the 7M cult’s perceived creepiness is the dancers' unfailing polish and flat if gleaming expressiveness.

From Salon • Jun. 6, 2024

Jughead was a favourite because of his unfailing devotion to food.

From BBC • Sep. 23, 2023

Refuge unfailing in which conflict tempered silenced reconciled.

From "The Sound and the Fury" by William Faulkner

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.