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muscae volitantes

British  
/ ˈmʌsiː vɒlɪˈtæntiːz /

plural noun

  1. pathol moving black specks or threads seen before the eyes, caused by opaque fragments floating in the vitreous humour or a defect in the lens

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of muscae volitantes

C18: New Latin: flying flies

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Some of the appearances of muscae volitantes, or of specks before the eyes, or occasionally of wavy lines, are due to disturbances of the circulation within the eyeball which cause corresponding disturbances of the optic nerve, with consequent apparent visions.

From Project Gutenberg

But when the speaker has such brilliant talent and literature as Margaret, she gives so many fine names to these merely sensuous and subjective phantasms, that the hearer is long imposed upon, and thinks so precise and glittering nomenclature cannot be of mere muscae volitantes, phoenixes of the fancy, but must be of some real ornithology, hitherto unknown to him.

From Project Gutenberg

A man will say that a smell is in his nose, a taste in his mouth, a singing in his ears, a creeping or a warmth in his skin; but if he is jaundiced, he does not say that he has yellow in his eyes, but that everything looks yellow; and if he is troubled with muscae volitantes, he says, not that he has specks in his eyes, but that he sees specks dancing before his eyes.

From Project Gutenberg