lengthen

verb

length·​en ˈleÅ‹(k)-thÉ™n How to pronounce lengthen (audio)
ˈlen(t)-
lengthened; lengthening
ˈleŋ(k)th-niŋ
ˈlen(t)th-;
  ˈleÅ‹(k)-thÉ™- 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-;
  ˈleÅ‹(k)-thÉ™- How to pronounce lengthen (audio)
ˈlen(t)-
noun
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
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.
Detention stays are lengthening in part because of the administration's decision last summer to restrict bond hearings in immigration court. Martin Kaste, NPR, 26 Mar. 2026 But having firefighters wait before starting preparations also delays when they can be dispatched to emergencies, which has lengthened response times — and has likely cost many lives across the city, the 60-page audit says. David Garrick, San Diego Union-Tribune, 26 Mar. 2026 Not to mention climate change, which lengthens growing seasons and increases pollen production. Tiffany Acosta, AZCentral.com, 25 Mar. 2026 Trouble is, the Legislature has had no trouble finding excuses to enact and renew an ever-lengthening list of exemptions. Martin Dyckman, The Orlando Sentinel, 22 Mar. 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

Cite this Entry

“Lengthen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lengthen. Accessed 27 Mar. 2026.

Kids Definition

lengthen

verb
length·​en ˈleÅ‹(k)-thÉ™n How to pronounce lengthen (audio)
ˈlen(t)-
lengthened; lengthening ˈleÅ‹(k)th-(É™-)niÅ‹ How to pronounce lengthen (audio)
ˈlen(t)th-
: to make or become longer
lengthener noun

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