blackleg

American  

[blak-leg] / ˈblækˌlɛg /

noun

1. Also called black quarter.  Also called symptomatic anthrax.  Veterinary Pathology. an infectious, often fatal disease of cattle and sheep, caused by the soil bacterium Clostridium chauvoei and characterized by painful, gaseous swellings in the muscles, usually of the upper parts of the legs.

2. Plant Pathology.

   1. a disease of cabbage and other cruciferous plants, characterized by dry, black lesions on the base of the stem, caused by a fungus, Phoma lingam.

   2. a disease of potatoes, characterized by wet, black lesions on the base of the stem, caused by a bacterium, Erwinia atroseptica.

3. a swindler, especially in racing or gambling.

4. British Informal. a strikebreaker; scab.

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verb (used with object)

British Informal.

blacklegged, blacklegging

1. to replace (a worker) who is on strike.

2. to refuse to support (a union, union workers, or a strike).

3. to betray or deceive (a person or cause).

verb (used without object)

blacklegged, blacklegging

1. British Informal. to return to work before a strike is settled.

blackleg British  

/ ˈblæklɛɡ /

noun

1. Also called: scab. 

   1. a person who acts against the interests of a trade union, as by continuing to work during a strike or taking over a striker's job

   2. ( as modifier )

      blackleg labour

2. Also called: black quarter.  an acute infectious disease of cattle, sheep, and pigs, characterized by gas-filled swellings, esp on the legs, caused by Clostridium bacteria

3. plant pathol

   1. a fungal disease of cabbages and related plants caused by Phoma lingam , characterized by blackening and decay of the lower stems

   2. a similar disease of potatoes, caused by bacteria

4. a person who cheats in gambling, esp at cards or in racing

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verb

1. to act against the interests of a trade union, esp by refusing to join a strike

Etymology

Origin of blackleg

First recorded in 1715–25; black + leg; the origin of nonliteral senses is unclear; cf. jackleg

Example Sentences

See Examples For:

blackleg blacklegged blacklegging

Phil Burbank is based on Savage’s step-uncle, eccentric William “Bill” Brenner, who died of blackleg just as Phil dies of anthrax.

From Washington Post ● Feb. 15, 2022

So we both knew the difference, when the blackleg hit.

From Nature ● Nov. 13, 2018

His first film as producer was The Angry Silence, an anti-trades union tract, in which Attenborough was a blackleg and yet a hero.

From The Guardian ● Aug. 24, 2014

Or they can be plants with virus or blackleg, or plants that are not "true-to-type", meaning they have the wrong morphology and are therefore too tall or deformed in another way, he adds.

From BBC ● Jun. 20, 2012

He spoke of shares and deals and swindling betrayal; of hope and fortune lost, and the false lead that puts a man on the chute and sets him off for a blackleg and a wanderer.

From Where the Pavement Ends by Russell, John

Anaplasmosis and Lyme disease are spread by western blacklegged ticks.

From Los Angeles Times ● Aug. 18, 2025

The reason is simple: Though blacklegged ticks feed on rodents when young, the adult ticks often feed and find their mate on the hides of deer.

From New York Times ● Jun. 29, 2023

For example, deer and rodent habitats are increasingly overlapping with human communities—and all three species are hosts for the blacklegged tick, also aptly named the deer tick.

From Scientific American ● Jun. 14, 2023

Borrelia travels on blacklegged ticks, which like to bite rodents and deer and humans.

From Slate ● Sep. 8, 2022

"I wad see that they blacklegged nae mair."

From The Underworld The Story of Robert Sinclair, Miner by Welsh, James C.

But you'll feel better in the end and your wife will be better right away and the children, and it won't be blacklegging on those who're trying to make things better.

From The Workingman's Paradise An Australian Labour Novel by Miller, John Maurice

But that's blacklegging and I'd sooner starve than blackleg.

From The Workingman's Paradise An Australian Labour Novel by Miller, John Maurice

There was a strike on at some building and he went on as a laborer, blacklegging.

From The Workingman's Paradise An Australian Labour Novel by Miller, John Maurice

She smiled grimly to watch Mrs. Macanany and viragoes like her pouring oil on the flames and drumming the weak-kneed up and screaming against "blacklegging" as a thing accurst.

From The Workingman's Paradise An Australian Labour Novel by Miller, John Maurice