White in the Eye
It is said that the devil has no white in his eyes, and hence the French locution, “Celui qui n`a point de blanc en l'oeil. ” “Do you see any white in my eye?” is asked by one who means to insinuate he is no fool or no knave- that is, he is not like the devil with no white in the eye.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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