The Collaborative International Dictionary of English v.0.48:

Champ \Champ\ (ch[a^]mp), v. t. [imp. & p. p. Champed
   (ch[a^]mt); p. pr. & vb. n. Champing.] [Prob, of Scand.
   orgin; cf. dial. Sw. k[aum]msa to chew with difficulty,
   champ; but cf. also OF. champier, champeyer, champoyer, to
   graze in fields, fr. F. champ field, fr. L. campus. Cf.
   Camp.]
   1. To bite with repeated action of the teeth so as to be
      heard.
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            Foamed and champed the golden bit.    --Dryden.
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   2. To bite into small pieces; to crunch. --Steele.
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