Synonyms

weaken

American

[wee-kuhn] / ˈwi kən /

verb (used with object)

to make weak or weaker.

Synonyms:

invalidate, minimize, impair, reduce, lower, diminish, lessen, deplete, exhaust, sap, undermine, enervate, debilitate, enfeeble

Antonyms:

strengthen
Phonetics. to change (a speech sound) to an articulation requiring less effort, as from geminate to nongeminate or from stop to fricative.

verb (used without object)

to become weak or weaker.

Synonyms:

sap, undermine, enervate, debilitate, enfeeble, invalidate, minimize, impair, reduce, lower, diminish, lessen, deplete, exhaust

Antonyms:

strengthen

weaken British

/ ˈwiːkən /

verb

to become or cause to become weak or weaker

"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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Etymology

Origin of weaken

First recorded in 1520–30; weak + -en ¹

Explanation

To weaken is to become less powerful or strong. When a storm weakens, the wind dies down and the torrential rain becomes a light drizzle. If you weaken physically, your strength diminishes: "I did great at the start of the obstacle course, but my arms began to weaken toward the end and I couldn't climb that last wall." You can also weaken in resolve or spirit, like when your sister's criticism of your art project weakens your confidence about including it in an exhibition. This verb comes from weak and its Germanic root meaning "yield" or "soft."

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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.

He said that investors want to see evidence that Adobe’s “freemium” funnel will translate to durable paid-subscriber growth, and not weaken the pricing power for its premium offerings.

From MarketWatch • Jul. 7, 2026

It is expected to weaken very slightly by the time it arrives on Monday over Guam and the Northern Marianas -- which are still recovering from Super Typhoon Sinlaku in April.

From Barron's • Jul. 3, 2026

Wilson in the 1960s attempted to weaken the department by creating the Department of Economic Affairs to handle long-term economic planning - but this ultimately failed.

From BBC • Jun. 30, 2026

However, as global shipping stabilizes, the positive situation is expected to weaken later in the year, and the company said uncertainties persist for the second half.

From The Wall Street Journal • Jun. 26, 2026

But prudence warned me neither to waste the time nor weaken my resolve by too much thought So I reached into my pocket and drew forth the small vial.

From "Ophelia" by Lisa Klein

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