waning

American  

[wey-ning] / weɪ nɪŋ /

adjective

1. decreasing in strength, intensity, etc..

   Many teens in focus groups expressed waning enthusiasm for social media.

2. declining in power, importance, prosperity, etc..

   The recent hacking of the retailer’s credit card system will have devastating implications for its already waning business.

3. drawing to a close; approaching an end.

   The bill will likely be passed in the waning days of this legislative session.

4. (of the moon) decreasing in the extent of its illuminated portion after the full moon.

   The crescent of fine white sand, wrapped around the bay, looked like a waning moon.

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noun

1. the process of decreasing, declining, or coming to an end.

   The Middle Ages occurred between the waning of the Roman Empire and the beginning of the Renaissance.

2. (of the moon) the process of decreasing in the extent of its illuminated portion after the full moon.

   Onion seeds are planted in the fall, during the waning of the Harvest Moon.

Other Word Forms

• unwaning
  adjective

Etymology

Origin of waning

First recorded before 900; wan(e) ( def. ) + -ing ² ( def. ) for the adjective senses; wan(e) ( def. ) + -ing ¹ ( def. ) for the noun senses

Explanation

If the moon was full, and now it's getting slimmer each night, it's a waning moon: it's getting gradually smaller. Waning can be used for anything that diminishes, like the brightness of the sunlight in the late afternoon, your interest in cartoons, or your influence over your teenage daughter's fashion choices. It comes from the Old English verb wǫnian, which means "to lessen."

Example Sentences

Waning trust in the predictability of American government policy feeds into bigger concerns.

From Barron's • Jan. 8, 2026

Waning appetite for tech stocks offset the positive impact of expectations for further interest-rate cuts after the Federal Reserve’s rate reduction last week.

From The Wall Street Journal • Dec. 15, 2025

Possible drawback: Waning motivation was among the criticisms lobbed at Shaw as he closed his Stanford career with back-to-back 3-9 seasons.

From Los Angeles Times • Feb. 10, 2024

Waning immunity occurs when protective antibodies and cellular defenses that were first stimulated by vaccine or infection diminish over time.

From National Geographic • Oct. 3, 2023

Waning existence, slow, irresistible decay, were impressed upon all around.

From Vineta The Phantom City by Werner, E. T. C. (Edward Theodore Chalmers)