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

Graphite is a key battery material, and securing alternative sources and production methods is part of efforts to strengthen US battery supply chains. — Neetika Walter, Interesting Engineering, 16 Sep. 2026

Working in a creative field only strengthened Hayley’s desire to make every element of the celebration feel intentional rather than checking off a list of wedding customs. — Ashley Vega, PEOPLE, 15 Sep. 2026

Many also argue that citizens’ assemblies strengthen democracy regardless of whether their recommendations become law. — Esther King, The Dial, 15 Sep. 2026

Open communication strengthens deterrence, prevents adversary miscalculation, and normalizes space operations alongside the other services. — Steven Beynon, ABC News, 15 Sep. 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