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

The roll-up top can be lengthened or tightened to fit your skis, accommodating up to two pairs of skis that are 203 centimeters long, as well as all the gear needed—from helmets and boots to gloves and ski gear. —Evie Carrick, Travel + Leisure, 15 Dec. 2025

Both characters become haunting part-marionette, part-human hybrids in the process (described aptly as the Lisaonette and the Abbionette by Adams), their limbs lengthening and eyes glowing. —Payton Turkeltaub, Variety, 11 Dec. 2025

From the best tubing formulations to lengthening, curling, and Bambi-eye-producing picks, these mascaras restore life to lashes of any age. —Jenny Berg, Vogue, 10 Dec. 2025

The story blooms and lengthens and sprawls, going from generation to generation, reckoning with the weight of lineage and history and wounds. —Literary Hub, Literary Hub, 9 Dec. 2025

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