chlo·​ro·​quine ˈklȯr-ə-ˌkwēn How to pronounce chloroquine (audio)
: an antimalarial drug C18H26ClN3 administered in the form of its bitter crystalline diphosphate

Example Sentences

Recent Examples on the Web That same day, the FDA granted a controversial emergency use authorization for hydroxychloroquine and chloroquine, allowing use against COVID-19. Beth Mole, Ars Technica, 24 Aug. 2022 The agency now says hydroxychloroquine and chloroquine have not been shown to be safe and effective for treating or preventing Covid19. Jacqueline Howard, CNN, 30 Sep. 2020 That's because a search for anti-malarial quinine alternatives during World War II led to the synthesis of compounds like chloroquine and hydroxychloroquine. Ella Lee, USA TODAY, 31 Jan. 2022 The drug is a single dose of tafenoquine (brand name Kozenis), administered along with the traditional chloroquine treatment. New York Times, 14 Mar. 2022 One of her team’s goals was to identify and systematically test substances used in traditional Chinese medicine in an effort to vanquish chloroquine-resistant malaria. Maggie Villiger, The Conversation, 4 Mar. 2022 The other three are chloroquine; a combination of lopinavir and ritonavir; and a combination of lopinavir, ritonavir, and interferon beta. Naomi Xu Elegant, Fortune, 28 Mar. 2020 The announcement from the agency is the latest blow to the hopes that hydroxychloroquine, as well as the related drug chloroquine, could provide patients an option at a time when there are too few treatments available for the virus. Andrew Joseph, STAT, 17 June 2020 At its core, hydroxychloroquine, along with its close cousin chloroquine, is an antimalarial medication that primarily treats and prevents the mosquito-borne infection by killing the microorganism (a plasmodium parasite) that causes it. Popular Science, 29 May 2020 See More

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

Word History


chlor- + quinoline

First Known Use

1946, in the meaning defined above

Time Traveler
The first known use of chloroquine was in 1946

Dictionary Entries Near chloroquine

Cite this Entry

“Chloroquine.” Dictionary, Merriam-Webster, Accessed 21 Mar. 2023.

Medical Definition


chlo·​ro·​quine ˈklōr-ə-ˌkwēn, ˈklȯr- How to pronounce chloroquine (audio)
: an antimalarial drug administered in the form of its diphosphate C18H26ClN3·2H3PO4 or hydrochloride C18H26ClN3·HCl

More from Merriam-Webster on chloroquine

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