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)-

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
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.
His telomeres, protective caps on chromosomes, lengthened in space, only to shorten rapidly upon return. Kaif Shaikh, Interesting Engineering, 16 Oct. 2025 The Airwrap Diffuse now features a wide-tooth comb, a new diffuser, and a round volumizing brush for good measure — here to lengthen your curls, reduce their overall frizz, and boost your mane’s fullness, respectively. Stacia Datskovska, Footwear News, 16 Oct. 2025 These circuitous routes greatly lengthen mission durations and limit launches to tight windows. Big Think, 15 Oct. 2025 Each year, the mining site crept farther south as deposits dwindled, lengthening her father’s commute. Literary Hub, 10 Oct. 2025 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

Browse Nearby Words

Cite this Entry

“Lengthen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lengthen. Accessed 21 Oct. 2025.

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 noun

More from Merriam-Webster on lengthen

Last Updated: - Updated example sentences
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