Synonyms of strengthen

strengthen

verb

ˈstreŋ(k)-thən 

1

as in to harden

to increase the ability of (as a muscle) to exert physical force

lifting weights every day will eventually strengthen your muscles

the army makes new recruits run for miles in order to strengthen them

Synonyms & Similar Words

• harden
• fortify
• toughen
• energize
• temper
• beef (up)
• invigorate
• vitalize
• tone (up)
• anneal
• firm (up)
• restrengthen

Antonyms & Near Antonyms

• weaken
• hurt
• impair
• cripple
• paralyze
• injure
• harm
• damage
• debilitate
• enfeeble
• undermine
• enervate
• incapacitate
• wear out
• break down
• undercut
• sap

2

as in to fortify

to make able to withstand physical hardship, strain, or exposure

required weeks of physical therapy to strengthen his arm enough to pitch for the team again

Synonyms & Similar Words

• fortify
• harden
• adjust
• bolster
• reinforce
• toughen
• inure
• steel
• adapt
• brace
• season
• boost
• support
• invigorate
• indurate
• vitalize
• enforce
• acclimate
• acclimatize
• temper
• immunize
• buttress
• anneal
• condition
• accustom
• train
• break in
• prop (up)
• habituate
• naturalize
• forearm
• limber (up)

Antonyms & Near Antonyms

• soften
• weaken
• exhaust
• emasculate
• sap
• cripple
• hamstring
• incapacitate
• sensitize
• enfeeble
• enervate
• debilitate

3

as in to enhance

to make markedly greater in measure or degree

encouraged the boarding school students to strengthen their ties with the community by doing public service

Synonyms & Similar Words

• enhance
• intensify
• deepen
• heighten
• consolidate
• reinforce
• broaden
• boost
• sharpen
• amplify
• expand
• redouble
• accentuate
• step up
• augment
• emphasize
• magnify
• extend
• lengthen
• beef (up)
• enforce
• accelerate
• maximize
• supplement
• enlarge
• amp (up)
• hasten
• quicken
• point (up)
• enliven
• restrengthen
• exacerbate
• stress
• aggravate
• jazz (up)

Antonyms & Near Antonyms

• reduce
• weaken
• decrease
• diminish
• moderate
• tone (down)
• lessen
• abate
• subdue
• recede
• alleviate
• subside
• lighten
• ease
• let up (on)
• wane
• dwindle
• taper (off)

4

as in to brace

to prepare (oneself) mentally or emotionally

strengthened herself for the moment she'd have to tell her friend that she had lost the borrowed necklace

Synonyms & Similar Words

• fortify
• brace
• ready
• nerve
• steel
• reinforce
• bolster
• enforce
• forearm
• poise
• psych (up)
• arm
• sustain
• encourage
• inure
• harden
• comfort
• buttress
• inspire
• toughen
• boost
• support
• season
• rouse
• embolden
• stir
• rally
• prop (up)
• hearten
• buoy (up)
• cheer (up)

Antonyms & Near Antonyms

• shake
• discourage
• undermine
• demoralize
• weaken
• daunt
• unnerve
• soften
• dishearten
• undercut
• debilitate
• psych (out)
• dispirit
• enfeeble
• sap
• tire
• prostrate
• enervate

5

as in to stiffen

to make more harsh, uncompromising, or severe

a bill was introduced to strengthen punishments for hate crimes

Synonyms & Similar Words

• stiffen
• toughen
• harden
• harshen

Antonyms & Near Antonyms

• ease
• lessen
• soften
• ameliorate
• moderate

Example Sentences

Recent Examples of strengthen

The second case centers on a campaign called Respect MO Voters that is pursuing a measure to strengthen the state’s initiative petition process, a form of direct democracy allowing voters to collect signatures and pass laws. — Kacen Bayless, Kansas City Star, 21 Aug. 2026

In a statement, PCL Construction spokesperson Angelo Dalmacio said the company is proud to have completed the 16th Street reconstruction project and that the collaboration strengthened the company’s relationship with the city and other stakeholders. — Katie Langford, Denver Post, 21 Aug. 2026

Abercrombie & Fitch is also reportedly looking for local partners in China to hand off the reins of its business there and strengthen its performance. — Laya Neelakandan, CNBC, 21 Aug. 2026

Earlier in the window Liverpool wanted to strengthen their midfield, but now that has taken a back seat. — James Pearce, New York Times, 21 Aug. 2026