prolong

verb

pro·​long prə-ˈlȯŋ How to pronounce prolong (audio)
prolonged; prolonging; prolongs
Synonyms of prolongnext

transitive verb

1
: to lengthen in time : continue
2
: to lengthen in extent, scope, or range
prolonger noun
Choose the Right Synonym for prolong

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 prolong in a Sentence

Additives are used to prolong the shelf life of packaged food. High interest rates were prolonging the recession.
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.
Yet once again, the results came back benign, prolonging the uncertainty and fear. Jordan Greene, PEOPLE, 7 Jan. 2026 While last year saw tens of thousands of flu deaths nationwide, more than the annual average, the season was prolonged, Wu said. Staff Report, Hartford Courant, 5 Jan. 2026 In a 2023 study presented at the European Hematology Association 2023 Congress in Frankfurt, Germany, researchers found that early treatment did not prolong overall survival compared to a placebo in patients with early, asymptomatic CLL. Melissa Rudy, FOXNews.com, 5 Jan. 2026 Essential safety tips for heavy rain Heavy rainfall may lead to flooding if prolonged or if there is excessive runoff. Bay Area Weather Report, Mercury News, 5 Jan. 2026 See All Example Sentences for prolong

Word History

Etymology

Middle English, from Middle French prolonguer, from Late Latin prolongare, from Latin pro- forward + longus long

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of prolong was in the 15th century

Browse Nearby Words

Cite this Entry

“Prolong.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/prolong. Accessed 8 Jan. 2026.

Kids Definition

prolong

verb
pro·​long prə-ˈlȯŋ How to pronounce prolong (audio)
: to make longer in time
prolonged the visit

More from Merriam-Webster on prolong

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