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Showing results for strengthen.
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.

These cells send signals that strengthen tumor cells.

From Science Daily • Apr. 5, 2026

“At a time of rampant threats to our democratic system, we must strengthen and defend the integrity of our elections to reaffirm that our government is of, by, and for the people,” she said.

From Los Angeles Times • Apr. 4, 2026

Microsoft plans to invest $10 billion in Japan over four years to develop AI infrastructure and strengthen cybersecurity.

From The Wall Street Journal • Apr. 3, 2026

"I do think that we should strengthen our cooperation on defence, security, energy, emissions and the economy," he replied.

From BBC • Apr. 1, 2026

“They can strengthen, you know, the longer they’re kept.”

From "Harry Potter and the Half-Blood Prince" by J.K. Rowling

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.