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

This lightweight cordless jump rope can provide an intense cardio workout while strengthening your muscles. —Bestreviews, Mercury News, 28 Mar. 2026

This grant will directly strengthen the infrastructure behind its weekly food distribution, increase the volume of food that can be recovered and provided, and ensure that families across the community continue to have consistent access to fresh, healthy food, according to a news release. —News Release, San Diego Union-Tribune, 28 Mar. 2026

Many are infused with hydrating and nourishing ingredients like vitamin E and castor oil to help strengthen lashes over time. —Lily Wohlner, Allure, 28 Mar. 2026

There is still time to fund Medicare Advantage at or above 2026 levels, ensure the growth rate reflects actual costs, and pursue reforms that genuinely strengthen the program. —Joe Hardy, Boston Herald, 28 Mar. 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