lengthen

American  

[lengk-thuhn, leng-, len-] / ˈlɛŋk θən, ˈlɛŋ-, ˈlɛn- /

verb (used with object)

1. to make longer; make greater in length.

   Synonyms:

   elongate

   Antonyms:

   shorten

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verb (used without object)

1. to become greater in length; grow long or longer.

lengthen British  

/ ˈlɛŋθən, ˈlɛŋkθən /

verb

1. to make or become longer

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Related Words

Lengthen, extend, stretch, prolong, protract agree in the idea of making longer. To lengthen is to make longer, either in a material or an immaterial sense: to lengthen a dress. To extend is to lengthen beyond some original point or so as to reach a certain point: to extend a railway line by a hundred miles. To stretch is primarily to lengthen by drawing or tension: to stretch a rubber band. Both prolong and protract mean especially to lengthen in time, and therefore apply to intangibles. To prolong is to continue beyond the desired, estimated, or allotted time: to prolong an interview. To protract is to draw out to undue length or to be slow in coming to a conclusion: to protract a discussion.

Other Word Forms

• lengthener noun
• outlengthen verb (used with object)
• unlengthened adjective

Etymology

Origin of lengthen

First recorded in 1490–1500; length + -en ¹

Explanation

To lengthen is to make something longer, either physically or in time. During the spring and early summer, the days lengthen, as sundown comes later and later. Mascara lengthens your eyelashes, and letting out your hem lengthens your jeans. As time goes by, your years of experience lengthen, and if you don't cut your hair or trim your beard, those lengthen as well. Lengthen dates from the 14th century — earlier, the verb was length, from a Germanic root that's also the basis of "long."

Example Sentences

Days lengthen and the Sun gets stronger, but when cold air moves in from the north, we can be quickly plunged back into wintry weather.

From BBC • Apr. 4, 2026

The complex mission would likely put American forces inside Iran for days or longer, and could lengthen the war, according to experts.

From The Wall Street Journal • Mar. 29, 2026

The hole had been a source of controversy all week following the decision to lengthen it from 236 to 273 yards.

From Los Angeles Times • Feb. 21, 2026

It would reduce entries, lengthen queue times and overturn a centuries-old policy, the report concluded.

From Barron's • Jan. 13, 2026

I thicken Astrid's nose hair, and lengthen it so it pokes from each nostril like the stubble on a man's chin.

From "The Belles" by Dhonielle Clayton

Related Words

• augment
• elongate
• expand
• prolong