The Collaborative International Dictionary of English v.0.48:

Crunch \Crunch\ (kr[u^]nch), v. i. [imp. & p. p. Crunched
   (kr[u^]ncht); p. pr. & vb. n. Crunching.] [Prob. of
   imitative origin; or cf. D. schransen to eat heartily, or E.
   scrunch.]
   1. To chew with force and noise; to craunch.
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            And their white tusks crunched o'er the whiter
            skull.                                --Byron.
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   2. To grind or press with violence and noise.
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            The ship crunched through the ice.    --Kane.
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   3. To emit a grinding or craunching noise.
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            The crunching and ratting of the loose stones. --H.
                                                  James.
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