Definition of Horner's syndrome in US English:

Horner's syndrome


  • A condition marked by a contracted pupil, drooping upper eyelid, and local inability to sweat on one side of the face, caused by damage to sympathetic nerves on that side of the neck.

    • ‘Other unusual but recognised presentations of cervical disc degeneration include headache, hemiparesis, hemidiaphragm paralysis, and Horner's syndrome because of involvement of the sympathetic chain.’
    • ‘An apical lung tumor, also known as a Pancoast tumor, may invade local neural structures and produce a characteristic syndrome of pain and possible Horner's syndrome.’
    • ‘He remains well seven years later, with a persistent left Horner's syndrome and lack of sweating on the left side of his head.’
    • ‘The swallowing difficulty begins suddenly, along with signs of cerebellar dysfunction and, sometimes, Horner's syndrome.’
    • ‘The clinical manifestations are broad but include ipsilateral ataxia, facial pain, dysphagia, loss of taste, vertigo, nausea, nystagmus, diplopia, Horner's syndrome, hiccups and contralateral pain and temperature loss.’


Early 20th century: named after Johann F. Horner (1831–86), Swiss ophthalmologist.


Horner's syndrome

/ˈhôrnərz ˌsindrōm/