The Collaborative International Dictionary of English v.0.48:

Blench \Blench\, v. i. [imp. & p. p. Blenched; p. pr. & vb. n.
   Blenching.] [OE. blenchen to blench, elude, deceive, AS.
   blencan to deceive; akin to Icel. blekkja to impose upon.
   Prop. a causative of blink to make to wink, to deceive. See
   Blink, and cf. 3d Blanch.]
   1. To shrink; to start back; to draw back, from lack of
      courage or resolution; to flinch; to quail.
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            Blench not at thy chosen lot.         --Bryant.
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            This painful, heroic task he undertook, and never
            blenched from its fulfillment.        --Jeffrey.
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   2. To fly off; to turn aside. [Obs.]
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            Though sometimes you do blench from this to that.
                                                  --Shak.
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