pro·​lif·​er·​ate | \ prə-ˈli-fə-ˌrāt How to pronounce proliferate (audio) \
proliferated; proliferating

Definition of proliferate

intransitive verb

1 : to grow by rapid production of new parts, cells, buds, or offspring
2 : to increase in number as if by proliferating : multiply

transitive verb

1 : to cause to grow by proliferating
2 : to cause to increase in number or extent as if by proliferating

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Other Words from proliferate

proliferation \ prə-​ˌli-​fə-​ˈrā-​shən How to pronounce proliferation (audio) \ noun
proliferative \ prə-​ˈli-​fə-​ˌrā-​tiv How to pronounce proliferative (audio) , prə-​ˈli-​f(ə-​)rə-​tiv How to pronounce proliferative (audio) \ adjective

Did You Know?

Proliferate came about in 1873 as a back-formation of "proliferation." That means that "proliferation" came first (we borrowed it from French in the 1850s) and was later shortened to form the verb "proliferate." Ultimately these terms come from Latin. The French adjective prolifère ("reproducing freely") comes from the Latin noun proles and the Latin combining form "-fer." Proles means "offspring" or "descendants," and -fer means "bearing." Both of these Latin forms gave rise to numerous other English words. "Prolific" and "proletarian" ultimately come from "proles"; "aquifer" and words ending in "-ferous" have their roots in "-fer."

Examples of proliferate in a Sentence

rumors about the incident proliferated on the Internet
Recent Examples on the Web Depending on their type, immune cells will proliferate, dwindle, change their activity, or produce more or less of certain proteins when exposed to additional estrogen—and these changes could make for a more powerful immune system. Grace Huckins, Wired, "Covid Kills More Men Than Women. Experts Still Can’t Explain Why," 9 July 2020 The groups said Facebook has taken some steps in the right direction but has broadly failed to properly enforce its policies and allowed hate speech to proliferate on its platform. Jeff Horwitz, WSJ, "Facebook Is Doing Too Little on Civil-Rights Concerns, Auditors Say," 8 July 2020 Rampant hate speech continues to proliferate all over Facebook, even as the company tries to increase its capacity to moderate content. Kate Cox, Ars Technica, "Employees, civil rights groups blast Facebook inaction on Trump statements," 3 June 2020 It's also been in hot water more recently for letting extremist groups proliferate on its platform. Allison Morrow, CNN, "Welcome to Irrational Exuberance Part Deux (aka the 2020 tech bubble)," 18 June 2020 Amenities like hot towels distributed by crew were one of the first things to go by the wayside when COVID-19 began to proliferate around the globe. Jessica Puckett, Condé Nast Traveler, "Flight Attendants Are Finally Being Recognized For Keeping Us Safe," 17 June 2020 The company and its CEO, Mark Zuckerberg, are facing criticism from users, competitors, civil rights organizations, and even employees for allowing racist content and hate speech to proliferate on the platform, amplified by President Donald Trump. Kate Cox, Ars Technica, "Employees, civil rights groups blast Facebook inaction on Trump statements," 3 June 2020 In March, as the coronavirus pandemic proliferated, the Detroit Three ordered that all employees whose jobs could be done remotely, do so. Jamie L. Lareau, Detroit Free Press, "Ford, GM and FCA to keep many white-collar employees working remotely," 4 June 2020 Many people who had routinely travelled to the Met or to the Philharmonic from the suburbs failed to resume their old habits; the seduction of staying home proved stronger, especially as digital offerings proliferated. Alex Ross, The New Yorker, "Coronavirus Concerts: The Music World Contends with the Pandemic," 14 Mar. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'proliferate.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of proliferate

1866, in the meaning defined at intransitive sense 1

History and Etymology for proliferate

back-formation from proliferation, from French prolifération, from proliférer to proliferate, from prolifère reproducing freely, from Latin proles + -fer -ferous

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Time Traveler for proliferate

Time Traveler

The first known use of proliferate was in 1866

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Statistics for proliferate

Last Updated

13 Jul 2020

Cite this Entry

“Proliferate.” Dictionary, Merriam-Webster, Accessed 15 Jul. 2020.

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More Definitions for proliferate


How to pronounce proliferate (audio)

English Language Learners Definition of proliferate

: to increase in number or amount quickly


pro·​lif·​er·​ate | \ prə-ˈlif-ə-ˌrāt How to pronounce proliferate (audio) \
proliferated; proliferating

Medical Definition of proliferate

intransitive verb

: to grow by rapid production of new parts, cells, buds, or offspring

transitive verb

: to cause to grow by proliferating

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