pro·​phy·​lac·​tic | \ ˌprō-fə-ˈlak-tik How to pronounce prophylactic (audio) also ˌprä- How to pronounce prophylactic (audio) \

Definition of prophylactic

 (Entry 1 of 2)

1 : guarding from or preventing the spread or occurrence of disease or infection
2 : tending to prevent or ward off : preventive



Definition of prophylactic (Entry 2 of 2)

: something prophylactic especially : a device and especially a condom for preventing venereal infection or conception

Other Words from prophylactic


prophylactically \ ˌprō-​fə-​ˈlak-​ti-​k(ə-​)lē How to pronounce prophylactic (audio) also  ˌprä-​ \ adverb

Synonyms for prophylactic

Synonyms: Adjective

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Examples of prophylactic in a Sentence

Adjective the prophylactic use of antibiotics the many prophylactic measures that city officials could have taken to reduce the scope of the disaster
Recent Examples on the Web: Adjective Meantime, hundreds of thousands of AstraZeneca’s Evusheld prophylactic treatment for immunocompromised patients are sitting on shelves at hospitals and infusion centers. Allysia Finley, WSJ, 1 Aug. 2022 In her view, those past rulings had clearly described Miranda as a distinct constitutional rule, not one that merely excluded evidence at trial as a prophylactic measure to enforce the Fifth Amendment, that created an accompanying right. Matt Ford, The New Republic, 4 July 2022 In a 6-3 ruling that fell along the usual ideological lines, the Court decided that the Miranda rule was purely prophylactic and did not fall under Section 1983’s scope. Matt Ford, The New Republic, 4 July 2022 Since the start of the pandemic, both prophylactic and postexposure measures have been rife with fraud. Hannah Zeavin, Harper’s Magazine , 22 June 2022 Some experts will consider prophylactic surgery if the woman needs surgery anyway, such as removing the ovaries as well during a hysterectomy for fibroids. Dr. Keith Roach, oregonlive, 9 June 2022 Those at high risk are typically considered for post-exposure or prophylactic vaccination with one of two vaccines that can prevent monkeypox. Beth Mole, Ars Technica, 3 June 2022 The bill also mandates coverage for MRIs, biopsies, prophylactic (preventative) mastectomies and breast reconstruction surgery, as well as routine ovarian cancer screenings. Susan Dunne, Hartford Courant, 6 May 2022 Immunocompromised people require additional vaccine doses, and in many cases other tools such as prophylactic monoclonal antibody therapies, to prevent Covid-19. John P. Moore And Luciana L. Borio, STAT, 25 Mar. 2022 Recent Examples on the Web: Noun Pfizer’s own trials found that the drug did not reduce the duration of COVID patients’ symptoms or work to prevent infection when taken as a prophylactic. Rachel Gutman-wei, The Atlantic, 30 July 2022 Paxlovid is not meant to be taken as a prophylactic after exposure to COVID-19 or if a patient is already hospitalized. Mary Kekatos, ABC News, 21 July 2022 One small prophylactic could be to pass a bill soon to let mail votes be preprocessed a few days before Election Day, as many other states permit. The Editorial Board, WSJ, 18 May 2022 An aversion to reality is, indeed, a poor prophylactic as Mr. O’Toole’s survey of six decades—1958 to 2018—demonstrates. Anna Mundow, WSJ, 17 Mar. 2022 Consuming crime as entertainment, then, can feel like a prophylactic against disaster. Kate Knibbs, Wired, 8 Mar. 2022 The constant machinations and heartless power struggles are fun to watch, but also serve as a kind of moral prophylactic, a way of investing in the competitions onscreen without being in danger of investing in the characters. Alison Willmore, Vulture, 24 Nov. 2021 They are currently authorized by the FDA to be used post-exposure but not as a prophylactic. Susannah Cullinane, CNN, 25 Oct. 2021 It has also been widely promoted as a coronavirus prophylactic and treatment. James Heathers, The Atlantic, 23 Oct. 2021 See More

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

First Known Use of prophylactic


1574, in the meaning defined at sense 1


circa 1641, in the meaning defined above

History and Etymology for prophylactic


borrowed from Medieval Latin prophylacticus, borrowed from Greek prophylaktikós, from prophylakt-, stem in nominal derivation of prophylássein "to keep guard before a place, be on guard, (middle voice) to be on one's guard against, take precautions against" + -ikos -ic entry 1 — more at prophylaxis


borrowed from Late Latin prophylacticon "protective measure against disease," borrowed from Late Greek prophylaktikón, noun derivative from neuter of Greek prophylaktikós prophylactic entry 1

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Time Traveler for prophylactic

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The first known use of prophylactic was in 1574

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Dictionary Entries Near prophylactic

prophets of doom



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Statistics for prophylactic

Last Updated

4 Aug 2022

Cite this Entry

“Prophylactic.” Dictionary, Merriam-Webster, Accessed 18 Aug. 2022.

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More Definitions for prophylactic


pro·​phy·​lac·​tic | \ ˌprō-fə-ˈlak-tik also ˌpräf-ə- \

Medical Definition of prophylactic

 (Entry 1 of 2)

1 : guarding from or preventing the spread or occurrence of disease or infection prophylactic therapy
2 : tending to prevent or ward off : preventive

Other Words from prophylactic

prophylactically \ -​ti-​k(ə-​)lē How to pronounce prophylactic (audio) \ adverb



Medical Definition of prophylactic (Entry 2 of 2)

: something (as a medicinal preparation) that is prophylactic especially : a device and especially a condom for preventing venereal infection or conception


pro·​phy·​lac·​tic | \ ˌprō-fə-ˈlak-tik, ˌprä- How to pronounce prophylactic (audio) \

Legal Definition of prophylactic

: designed or tending to prevent harm or wrong a prophylactic rule against profiting from inside information

More from Merriam-Webster on prophylactic Encyclopedia article about prophylactic


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