heart·​worm | \ ˈhärt-ˌwərm How to pronounce heartworm (audio) \

Definition of heartworm

: a filarial worm (Dirofilaria immitis) that is a parasite especially in the right heart of dogs and is transmitted by mosquitoes also : infestation or disease caused by the heartworm

Examples of heartworm in a Sentence

Recent Examples on the Web Heartworms cause serious complications in the heart and lungs of dogs, and treatment for heartworm disease is risky. People Staff, PEOPLE.com, 5 May 2022 Dogs and cats of all ages are welcome to come receive a wellness check as well as rabies vaccinations, core vaccinations, basic deworming and heartworm testing. Hartford Courant, 5 May 2022 Fortunately, many heartworm prevention products also protect dogs from common intestinal parasites. People Staff, PEOPLE.com, 5 May 2022 The current longest resident of AHS, sweet Worldwide has been receiving plenty of tender care in a Foster Hero home while undergoing treatment for heartworm. The Arizona Republic, 23 Feb. 2022 In veterinary medicine, it is used to prevent and treat heartworm. Joshua Cohen, Forbes, 1 Jan. 2022 Ivermectin has historically been used to treat diseases such as river blindness or scabies in humans and, in some formulations, to prevent heartworm disease and other infestations in animals. al, 18 Jan. 2022 Animal ivermectin is approved to prevent heartworm disease and treat certain internal and external parasites and only approved by the FDA to treat people with conditions caused by parasitic worms. Christopher Kuhagen, USA TODAY, 29 Dec. 2021 Different forms of the drug are used to treat animals for heartworm and other parasites. Robert Mccoppin, chicagotribune.com, 24 Dec. 2021 See More

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

First Known Use of heartworm

1877, in the meaning defined above

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The first known use of heartworm was in 1877

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Last Updated

26 May 2022

Cite this Entry

“Heartworm.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/heartworm. Accessed 29 Jun. 2022.

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More Definitions for heartworm


heart·​worm | \ -ˌwərm How to pronounce heartworm (audio) \

Medical Definition of heartworm

1 : a filarial worm of the genus Dirofilaria (D. immitis) that is especially common in warm regions, lives as an adult in the right heart especially of dogs, and discharges active larvae into the circulating blood whence they may be picked up by mosquitoes and transmitted to other hosts and that may infect humans causing local pulmonary infarction but does not achieve sexual maturity in the human organism
2 : infestation with or disease especially of dogs caused by the heartworm, resulting typically in gasping, coughing, and nervous disorder, and when severe commonly leading to death

More from Merriam-Webster on heartworm

Britannica.com: Encyclopedia article about heartworm


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