Crossword Genius

Falls that can impair one's vision (8)

Ross

I believe the answer is:

cataract

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'falls' is the definition.
(synonyms)

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(Other definitions for cataract that I've seen before include "can obstruct your view" , "may impair the vision" , "Waterfall - opacity of the eye" , "A real downpour" , "(Nile) waterfall" .)

I've seen this clue in The Times.
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