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

Walking lunges, high-knee marches and squats in shallow water strengthen the quadriceps, hamstrings, glutes and calves. — Patricia Neligan, AJC.com, 27 July 2026

Madrid have had a busy summer with Jose Mourinho returning as head coach and the club moving quickly to strengthen the squad with Marc Cucurella, Bernardo Silva, Ibrahima Konate and Denzel Dumfries among the arrivals. — David Ornstein, New York Times, 26 July 2026

Trakas, Senior Community Relations Representative for Cleveland-Cliffs, supported OE’s efforts on a grant application for the Shared Table Food Pantry, helping strengthen food security initiatives for the individuals OE serves, a release said. — Post-Tribune, Chicago Tribune, 26 July 2026

If enthusiasm has been carrying a weak structure, strengthen the structure. — Tarot.com, The Orlando Sentinel, 26 July 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