lengthen

verb

length·​en ˈleŋ(k)-thən How to pronounce lengthen (audio)
ˈlen(t)-
lengthened; lengthening
ˈleŋ(k)th-niŋ, 
ˈlen(t)th-;
  ˈleŋ(k)-thə- How to pronounce lengthen (audio)
ˈlen(t)-
Synonyms of lengthennext

transitive verb

: to make longer

intransitive verb

: to grow longer
lengthener
ˈleŋ(k)th-nər, 
ˈlen(t)th-;
  ˈleŋ(k)-thə- How to pronounce lengthen (audio)
ˈlen(t)-
noun

Synonyms of lengthen

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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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
These genes influence how quickly bones lengthen, how long each finger becomes, and how the joints and tendons are shaped. — Steven Lautzenheiser, The Conversation, 6 July 2026 These large-range movements keep your body moving through the stretch, shortening and lengthening your muscles. — Hannah Harper, Health, 1 July 2026 This cropped wide-leg style is made from lightweight denim that feels especially suited for summer, with a leg-lengthening high waist and relaxed shape. — Jeaneen Russell, PEOPLE, 1 July 2026 Whether they’re kitten-heeled or a tall pump, this shoe design lengthens the leg, offsetting the Bermuda shorts to create a streamlined silhouette. — René Chávez Esparza, Glamour, 3 July 2026 See All Example Sentences for lengthen

Word History

First Known Use

14th century, in the meaning defined at transitive sense

Time Traveler
The first known use of lengthen was in the 14th century

Rhymes for lengthen

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Browse Nearby Words

length-breadth index
lengthen
lengthener
See all Nearby Words

Cite this Entry

“Lengthen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lengthen. Accessed 7 Jul. 2026.

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Kids Definition

lengthen

verb
length·​en ˈleŋ(k)-thən How to pronounce lengthen (audio)
ˈlen(t)-
lengthened; lengthening ˈleŋ(k)th-(ə-)niŋ How to pronounce lengthen (audio)
ˈlen(t)th-
: to make or become longer
lengthener
ˈleŋ(k)th-(ə-)nər How to pronounce lengthen (audio)
ˈlen(t)th-
noun

More from Merriam-Webster on lengthen

Nglish: Translation of lengthen for Spanish Speakers

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