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

transitive verb

: to lengthen in time : continue
: 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 Russia will use its global assets and instruments to prolong the war. Michael Kimmage and Hanna Notte, Foreign Affairs, 1 Sep. 2023 One distressing theory suggests that failure to reach a pact by the middle of next month will further prolong the work stoppages, because the media companies will have essentially given up on their financial fourth quarters. Ryan Faughnder, Los Angeles Times, 29 Aug. 2023 Power outages, which were expected to be widespread and prolonged because of the storm’s heavy winds, began just before noon Sunday in coastal North County. David Garrick, San Diego Union-Tribune, 21 Aug. 2023 And so if the bleaching is prolonged for a prolonged period of time, that coral then begins to die. Dana Taylor, USA TODAY, 20 Aug. 2023 Auburn’s quarterback decision has prolonged beyond the initial time frames coaches set. Matt Cohen |, al, 15 Aug. 2023 Controlling high blood pressure would prolong the lives of the nearly 500,000 Americans who die from this disease each year. Lola Butcher, Smithsonian Magazine, 25 Aug. 2023 As climate change brings hotter temperatures and prolonged dry spells to the tropics, the canal's long-term viability is now a subject of concern for many. Ben Tracy, CBS News, 23 Aug. 2023 There are multiple theories as to why prolonged PPI use might increase dementia risk, Lutsey said. Maggie O'Neill, Health, 22 Aug. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'prolong.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


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

Dictionary Entries Near prolong

Cite this Entry

“Prolong.” Dictionary, Merriam-Webster, Accessed 25 Sep. 2023.

Kids Definition


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

More from Merriam-Webster on prolong

Last Updated: - Updated example sentences
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