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Definitions

strengthen

[strengk-thuhn, streng-, stren-] / ˈstrɛŋk θən, ˈstrɛŋ-, ˈstrɛn- /
VERB
make more forceful, powerful
Synonyms
STRONGEST
bolster build up enhance enlarge establish extend heighten increase intensify invigorate reinforce restore set up step up support sustain toughen
STRONG
add anneal ascend brace buttress confirm corroborate empower fortify harden justify mount multiply regenerate rejuvenate renew rise steel substantiate temper tone wax
WEAK
add fuel to fire make firm sinew tone up
Antonyms
STRONGEST
abridge condense curtail decrease destroy diminish halt hinder lessen let down lower reduce shrink slow subtract undermine weaken
STRONG
contradict decline deny descend disprove drop fall kill reject ruin slump soften
WEAK
break down discourage dishearten dissuade hurt
VERB
encourage, hearten
Synonyms
STRONGEST
consolidate invigorate restore toughen uphold
STRONG
animate back bloom brace burgeon cheer embolden enliven flourish flower fortify gird harden inspirit nerve nourish prepare prosper rally ready refresh rejuvenate steel substantiate temper thrive
WEAK
back up bear out brace up carry weight enhearten gather resources give weight
Antonyms
STRONG
discourage dishearten dissuade fail kill languish let go lose neglect ruin shrink shrivel soften weaken
WEAK
break down hurt

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.

"But a balanced outcome that reaffirms core commitments and set out practical steps forward would strengthen the integrity of the NPT," he said.

From Barron's • Apr. 27, 2026

"This is why we keep exploring -- to unlock the secrets of the deep and better understand how the ocean and its resources can drive economic growth, strengthen our national security, and sustain our planet."

From Science Daily • Apr. 27, 2026

“The lesson that can be taken away is just thinking about how to harden and strengthen security at future events when you have so many high-profile people,” she said.

From Los Angeles Times • Apr. 26, 2026

He said European countries were currently "doing a great deal to strengthen Nato".

From BBC • Apr. 24, 2026

‘Already the Sun is climbing to noon, and I feel the need of something to strengthen me.’

From "The Fellowship of the Ring" by J.R.R. Tolkien

Vocabulary lists containing strengthen

President Obama's second inaugural address

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Spelling Practice, Unit 2

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