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

The dozens of dogs where immediately rushed to GBHS, where veterinarians, vet students from Auburn University and vet techs were standing by to provide exams, heartworm treatment, flea and tick medication and other medical care. Kelli Bender, PEOPLE.com, "More than 80 Dogs, Including Days-Old Puppies, Rescued from Excrement-Caked Puppy Mill in Alabama," 10 July 2018 While the hound was in relativity good health, his heartworm test came back positive and was subsequently placed on the shelter’s euthanasia list. Madeline Farber, Fox News, "Ohio shelter dog's 'freedom ride' photo goes viral," 11 May 2018 Both of them are neutered, up to date on vaccinations, microchipped, have been heartworm tested (both are negative) and are licensed with Maricopa County Animal Care and Control. Arizona Republic, azcentral, "Give one of these Valley rescue pets a forever home this week," 22 June 2018 Ginger was taken to Summer Street Animal Hospital for care, started a heartworm treatment regimen and soon warmed up to Glick. Saryn Chorney, PEOPLE.com, "Missing Dog Lost in Woods Survives Three Years on Fast Food and Car Wash Water, Finally Reunites with Family," 19 June 2018 The parasite, a cousin of heartworm, is found in Europe, Africa and Asia and can grow to as long as six inches. NBC News, "Moving lump in woman's face was a worm, doctors say," 22 June 2018 Dirofilaria are usually found in dogs or other carnivores, according to the CDC, but have been known to infest humans, too, especially in Europe and with certain species - D. repens, D. tenuis and D. immitis (better known as heartworm in dogs). Lindsey Bever, chicagotribune.com, "Blemishes moving around Russian woman's face turned out to be a parasitic worm," 22 June 2018 The Centers for Disease Control and Prevention reports that D. repens are not found in the US, but the country does harbor relatives D. immitis, which cause heartworm disease in dogs, and D. tenuis, which affect raccoons. Beth Mole, Ars Technica, "Selfies show worm slithered through woman’s face for 2 weeks," 22 June 2018 Cristina's creatures run the gamut and include the unadoptable, some elderly pets, and those with such varied medical issues as bladder stones and heartworm-positive diagnoses. Christian Scaffidi, NOLA.com, "Pontchartrain Humane Society Pet Adoption Day is May 12," 9 May 2018

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.

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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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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

Rhyming Dictionary: Words that rhyme with heartworm

Britannica.com: Encyclopedia article about heartworm

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