heartworm

noun

heart·​worm ˈhärt-ˌwərm 

: 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

He was estimated to be around 8 to 10 years old, with a severe flea allergy (causing his hair loss), was missing several teeth and was heartworm positive. —Thomas G. Moukawsher, Newsweek, 30 Jan. 2025

Gold plan: Includes annual wellness exams, vaccinations, flea and heartworm prevention, deworming and dental cleaning, with an annual benefit limit is $250. —Liz Knueven, CNBC, 18 Jan. 2025

Platinum plan: Same benefits as Gold, plus spaying/neutering, urinalysis and blood testing, and flea, tick and heartworm protection, as well as $25 for health certificates. —Liz Knueven, CNBC, 18 Jan. 2025

Barney has heartworm disease, a painful condition requiring dangerous treatment. —Dan Perry, Newsweek, 5 Jan. 2025

Word History

First Known Use

1877, in the meaning defined above

Medical Definition

heartworm

noun

heart·​worm -ˌwərm 

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