Definition of myasthenia in English:



  • 1A condition causing abnormal weakness of certain muscles.

    ‘Louise suffers from osteoporosis and myasthenia, a muscle weakness which means she needs to sleep for about four hours after every riding lesson.’
    • ‘Surgical removal of the thymus gland is performed in patients with a thymoma and can also help some other patients, especially those who develop myasthenia before the age of about 45.’
    • ‘Unlike myasthenia, however, it is associated with improved strength with repeated muscle activity.’
    • ‘He is receiving plasmapheresis as part of his treatment for myasthenia.’
    1. 1.1A rare chronic autoimmune disease marked by muscular weakness without atrophy, and caused by a defect in the action of acetylcholine at neuromuscular junctions.
      ‘It has been useful in treating autoimmune diseases such as myasthenia gravis.’
      • ‘The drug was first approved by the FDA as a treatment for myasthenia gravis, a chronic neuromuscular disease.’
      • ‘Congenital myasthenia gravis is rare and can be excluded by maternal and neonatal history.’
      • ‘Patients with myasthenia gravis typically present with weakness, developing with or aggravated by exertion.’
      • ‘Doctors said a recent checkup indicated he was suffering from an auto-immune disorder called myasthenia gravis, symptoms of which began appearing at the end of last month.’



/ˌmīəsˈTHēnēə/ /ˌmaɪəsˈθiniə/


Mid 19th century modern Latin, from Greek mus ‘muscle’+ asthenia.