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Definitions

weaken

[wee-kuhn] / ˈwi kən /
VERB
reduce the strength of
Synonyms
STRONGEST
abate decline decrease depress dilute diminish dwindle halt impair lessen lower reduce sap soften undermine wane
STRONG
adulterate crumble cut debase debilitate devitalize droop enervate exhaust fade fail faint flag impoverish invalidate languish limp lose minimize mitigate moderate relapse relax temper thin tire totter tremble vitiate wilt
WEAK
break up ease up give way lose spirit slow down thin out water down
Antonyms
STRONGEST
aid assist compliment develop encourage enlarge expand extend grow help increase praise prolong raise rise strengthen
STRONG
achieve activate aggravate agitate animate clean energize enhance excite free improve incite invigorate purify refresh succeed win
WEAK
build up

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.

As these weaken and stiffen over time it can affect walking, talking, eating and breathing.

From BBC • Apr. 10, 2026

It can also weaken statistical results and fails to reveal how languages change over time.

From Science Daily • Apr. 5, 2026

The risk/reward of staying in private funds isn’t good because fund performance has started to weaken and there is a risk of higher redemptions in the coming quarters.

From Barron's • Apr. 3, 2026

“On the one hand, raising the policy rate to bring down inflation could weaken the economy further. On the other hand, lowering rates to support the economy could risk pushing inflation even higher.”

From The Wall Street Journal • Apr. 1, 2026

Others thought that if their bodies were going to weaken in space, they should start out as strong as possible, and that meant exercise.

From "Flying to the Moon: An Astronaut's Story" by Michael Collins