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

Through collective giving, the fund directs resources to programs that strengthen community well-being and quality of life, the news release stated. —Dawn Giangiulio, San Diego Union-Tribune, 28 Feb. 2026

DiStefano said the office started holding workshops for faculty to talk about their research and strengthen relationships with industry partners. —Sara Bedigian, Hartford Courant, 28 Feb. 2026

Choose fair terms to strengthen your financial confidence. —Tarot.com, The Orlando Sentinel, 28 Feb. 2026

Pozzo joined as deputy CEO in July 2025, alongside a 25-million-euro capital increase to strengthen the balance sheet and support the company’s strategic reset. —Alexandra Harrell, Sourcing Journal, 27 Feb. 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