The Collaborative International Dictionary of English v.0.48:

Blear \Blear\, v. t. [imp. & p. p. Bleared; p. pr. & vb. n.
   Blearing.] [OE. bleren; cf. Dan. plire to blink, Sw. plira
   to twinkle, wink, LG. plieren; perh. from the same root as E.
   blink. See Blink, and cf. Blur.]
   To make somewhat sore or watery, as the eyes; to dim, or
   blur, as the sight. Figuratively: To obscure (mental or moral
   perception); to blind; to hoodwink.
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         That tickling rheums
         Should ever tease the lungs and blear the sight.
                                                  --Cowper.
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   To blear the eye of, to deceive; to impose upon. [Obs.]
      --Chaucer.
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