adjective
-
not failing; unflagging
-
continuous or unceasing
-
sure; certain
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
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
Franklin was less concerned with unfailing rectitude than Washington, yet he also lived by a code of public service and personal honor that made him one of the most celebrated men of his times.
From Seattle Times • Aug. 18, 2023
The stride length, the quickness of the foot feints, all clearly revealed to his unfailing eye, made him reassess his second conclusion.
From "The Princess Bride" by William Goldman
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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.