lengthen

verb

length·​en ˈleŋ(k)-thən 

ˈlen(t)-

lengthened; lengthening

ˈleŋ(k)th-niŋ, 

ˈlen(t)th-;

  ˈleŋ(k)-thə- 

ˈlen(t)-

transitive verb

: to make longer

intransitive verb

: to grow longer

lengthener

ˈleŋ(k)th-nər, 

ˈlen(t)th-;

  ˈleŋ(k)-thə- 

ˈlen(t)-

noun

Synonyms of lengthen

• extend
• prolong
• increase
• stretch
• elongate

Choose the Right Synonym for lengthen

extend, lengthen, prolong, protract mean to draw out or add to so as to increase in length.

extend and lengthen imply a drawing out in space or time but extend may also imply increase in width, scope, area, or range.

extend a vacation

extend welfare services

lengthen a skirt

lengthen the workweek

prolong suggests chiefly increase in duration especially beyond usual limits.

prolonged illness

protract adds to prolong implications of needlessness, vexation, or indefiniteness.

protracted litigation

Examples of lengthen in a Sentence

The days lengthened with the approach of spring.

Proper care will lengthen the life of the engine.

lengthen a pair of trousers

Recent Examples on the Web

These stretchy, flattering jeans come in a range of washes that are both leg-lengthening and easy to move around in. —Annie Blackman, InStyle, 7 Apr. 2026

Celebs like Jennifer Aniston and Jennifer Garner have recently worn this leg-lengthening style, which is sleek without feeling tight or restrictive. —Jacqueline Tempera, PEOPLE, 7 Apr. 2026

The Padres are banking on more of that to lengthen the lineup for the top of an order that is also not living up to expectations, but the Padres catchers have continued to provide value on defense throughout their sluggish start at the plate. —Jeff Sanders, San Diego Union-Tribune, 5 Apr. 2026

The bill would essentially prioritize people committed under the new process over those waiting for competency restoration services, potentially lengthening the competency waitlist, said Jack Johnson, public policy liaison at Disability Law Colorado. —Shelly Bradbury, Denver Post, 5 Apr. 2026

Word History

First Known Use

14th century, in the meaning defined at transitive sense

Rhymes for lengthen

• strengthen

Kids Definition

lengthen

verb

length·​en ˈleŋ(k)-thən 

ˈlen(t)-

lengthened; lengthening ˈleŋ(k)th-(ə-)niŋ 

ˈlen(t)th-

: to make or become longer

lengthener

ˈleŋ(k)th-(ə-)nər 

ˈlen(t)th-

noun