screwworm

noun screw·worm \ ˈskrü-ˌwərm \

Definition of screwworm

1 : a blowfly (Cochliomyia hominivorax) of the warmer parts of America whose larva develops in sores or wounds or in the nostrils of mammals including humans with serious or sometimes fatal results; especially : its larva

2 : any of several flies other than the screwworm and especially their larvae which parasitize the flesh of mammals

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Recent Examples of screwworm from the Web

An outbreak of grisly screwworm infected the planet’s last herd of Key deer on and around Big Pine in 2016, killing about 135 deer.

— jenny staletovich, miamiherald, "A third of nation’s wildlife at risk of disappearing, report says | Miami Herald," 29 Mar. 2018
In Florida, a screwworm outbreak killed 135 Key deer last year and white-nose syndrome among bats has killed more than 5 million.

— jenny staletovich, miamiherald, "A third of nation’s wildlife at risk of disappearing, report says | Miami Herald," 29 Mar. 2018
First, after a nasty infection by the larvae of a parasitic fly called the screwworm began to infest the population in the fall of 2016.

— david goodhue, miamiherald, "What happened to the tiny Key deer during Hurricane Irma?," 11 Sep. 2017
From the 1950s to the early 2000s, a massive effort went into eradicating invasive screwworms—which burrow into the flesh of livestock—from the United States down to Panama.

— sarah zhang, The Atlantic, "Genetically Modified Moths Come to New York," 8 Sep. 2017
The infestation was finally eliminated after scientists released roughly 124 million sterile screwworm flies to mate with wild flies.

— david goodhue, miamiherald, "What happened to the tiny Key deer during Hurricane Irma?," 11 Sep. 2017
The herd faced a potential extinction event last year when the first screwworm infestation in the U.S. in 30 years.

— Bloomberg.com, "URGENT: The Latest: Dutch Government: 4 Irma Deaths on St. Maarten," 10 Sep. 2017

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

First Known Use of screwworm

1846

in the meaning defined at sense 1

See Words from the same year

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Medical Dictionary

screwworm

noun screw·worm \ ˈskrü-ˌwərm \

medical Definition of screwworm

1 : either of two dipteran flies of the genus Cochliomyia:

a : one (C. hominivorax) of the warmer parts of America whose larva develops in sores or wounds or in the nostrils of mammals including humans with serious or sometimes fatal results; especially : its larva

b : secondary screwworm

2 : a dipteran fly of the genus Chrysomya (C. bezziana) that causes myiasis in Africa and southern Asia