my·​as·​the·​nia | \ ˌmī-əs-ˈthē-nē-ə How to pronounce myasthenia (audio) \

Definition of myasthenia

: muscular debility also : myasthenia gravis

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Other Words from myasthenia

myasthenic \ ˌmī-​əs-​ˈthe-​nik How to pronounce myasthenic (audio) \ adjective or noun

Examples of myasthenia in a Sentence

Recent Examples on the Web That doctor argued that although myasthenia often causes weakness in the muscles of the eyes and mouth — not unlike what this woman had — that weakness usually comes and goes. Lisa Sanders, M.d., New York Times, "All Signs Pointed to a Stroke. Then the Tests Come Back Negative.," 26 Sep. 2017 His death at the age of 74 came after a long battle with the physically debilitating illness myasthenia gravis and after a public-service career that spanned four decades. Sheldon S. Shafer, The Courier-Journal, "Former mayor, judge-executive Armstrong remembered at service," 7 July 2017 Smith had battled the nerve disease myasthenia gravis for many years. Joseph Longo,, "Roger Smith, star of '77 Sunset Strip,' husband of actress Ann-Margret, dies at 84," 6 June 2017 Mr. Smith, who had given up performing to manage his wife’s career, had been diagnosed with myasthenia gravis, an autoimmune neuromuscular disease that causes extreme weakness. Adam Bernstein, Washington Post, "Roger Smith, a star of TV’s ‘77 Sunset Strip,’ dies at 84," 5 June 2017 After a year and a half of tests and several brutal eye surgeries, he was given a diagnosis of myasthenia gravis, a rare autoimmune disease that interferes with the way nerves and muscles communicate. Kim Severson, New York Times, "Chef Sean Brock Puts Down the Bourbon and Begins a New Quest," 3 July 2017 Trollious Harris, who has spent most of her life a few blocks from the Taylors, suffers from myasthenia gravis, another autoimmune condition, which has caused her muscles to weaken. Charles P. Pierce, Esquire, "Meanwhile, These Americans Are Being Poisoned," 19 May 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'myasthenia.' 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 myasthenia

circa 1833, in the meaning defined above

History and Etymology for myasthenia

New Latin

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Time Traveler for myasthenia

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The first known use of myasthenia was circa 1833

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Cite this Entry

“Myasthenia.” Dictionary, Merriam-Webster, Accessed 30 Sep. 2020.

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More Definitions for myasthenia


my·​as·​the·​nia | \ ˌmī-əs-ˈthē-nē-ə How to pronounce myasthenia (audio) \

Medical Definition of myasthenia

: muscular debility also : myasthenia gravis

Other Words from myasthenia

myasthenic \ -​ˈthen-​ik How to pronounce myasthenic (audio) \ adjective

More from Merriam-Webster on myasthenia

Britannica English: Translation of myasthenia for Arabic Speakers

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