✨📕 The NEWThe NEW Collegiate Dictionary, 12th Edition Over 5,000 words added — Buy Now! Collegiate DictionaryBuy Now!

prolong

verb

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

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.
Protein and fat slow digestion, which can delay the blood sugar peak and prolong elevated blood glucose levels for hours. Verywell Health, 24 Nov. 2025 Barney, now 31, underwent radiation and chemotherapy to prolong his life. Vanessa Etienne, PEOPLE, 21 Nov. 2025 Their 16-year-old daughter fears prolonged detention for her parents even more than the possibility of them being deported to Mexico. CBS News, 21 Nov. 2025 Could Kelce prolong his pro football career? Blair Kerkhoff, Kansas City Star, 21 Nov. 2025 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 27 Nov. 2025.

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

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!