black·​leg ˈblak-ˌleg How to pronounce blackleg (audio)
: a usually fatal toxemia especially of young cattle caused by a soil bacterium (Clostridium chauvoei)
: a cheating gambler : swindler
chiefly British : a worker hostile to trade unionism or acting in opposition to union policies : scab

Examples of blackleg in a Sentence

Recent Examples on the Web Herding Sheep with Bill There was no contradicting his calendar Of superstitions – the feast of some saint or other The sheep had to be herded off the mountain, Culled and counted, dipped and Doctored with shots for blackleg. Hartford Courant,, 11 Mar. 2018

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'blackleg.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

circa 1722, in the meaning defined at sense 1

Time Traveler
The first known use of blackleg was circa 1722

Dictionary Entries Near blackleg

Cite this Entry

“Blackleg.” Dictionary, Merriam-Webster, Accessed 1 Dec. 2023.

Medical Definition


black·​leg ˈblak-ˌleg, -ˌlāg How to pronounce blackleg (audio)
: an enzootic usually fatal toxemia especially of young cattle caused by toxins produced by an anaerobic soil bacterium of the genus Clostridium (C. chauvoei synonym C. feseri)

called also black quarter, quarter evil, quarter ill, symptomatic anthrax

compare black disease, malignant edema

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