strengthen

verb

strength·​en ˈstreŋ(k)-thən 

ˈstren(t)-

strengthened; strengthening

ˈstreŋ(k)th-niŋ, 

ˈstren(t)th-;

  ˈstreŋ(k)-thə- 

ˈstren(t)-

transitive verb

: to make stronger, more forceful, more effective, etc.

These exercises will strengthen your abdominal muscles.

intransitive verb

: to become stronger, more forceful, more effective, etc.

The winds are expected to strengthen.

strengthener

ˈstreŋ(k)th-nər, 

ˈstren(t)th-;

  ˈstreŋ(k)-thə- 

ˈstren(t)-

noun

Synonyms of strengthen

• harden
• fortify

Examples of strengthen in a Sentence

These exercises will strengthen your stomach muscles.

He takes herbs to strengthen his immune system.

The development of new electronic products has strengthened the company's position as the leader in digital technology.

Holidays often serve to strengthen bonds between family members.

Their financial situation strengthened her determination to find a new career.

The team has been strengthened by the addition of several new players.

The winds are expected to strengthen.

The economy is slowly strengthening.

The Canadian dollar is strengthening against the U.S. dollar.

The trade restrictions will strengthen the pound.

Recent Examples on the Web

As the Moon moves through your 12th House of Solitude, quiet focus strengthens your output and steadiness. —Tarot.com, The Orlando Sentinel, 29 Apr. 2026

The king said the Easter season strengthens his hope. —Kathryn Palmer, USA Today, 29 Apr. 2026

Zuckerberg has said the investments will strengthen the ad business by making recommendations more relevant and improving the way ads are targeted to increase the time consumers spend on its platforms including Instagram, WhatsApp, and Facebook. —Amanda Gerut, Fortune, 29 Apr. 2026

The concept reflects a broader shift toward scalable, expendable unmanned systems, as Japan looks to strengthen its defense capabilities with practical, cost-efficient solutions. —Jijo Malayil, Interesting Engineering, 29 Apr. 2026

Word History

First Known Use

15th century, in the meaning defined at transitive sense

Rhymes for strengthen

• lengthen

Kids Definition

strengthen

verb

strength·​en ˈstreŋ(k)-thən 

strengthened; strengthening ˈstreŋ(k)th-(ə-)niŋ 

: to make or become stronger

strengthener

-(ə-)nər 

noun