The Collaborative International Dictionary of English v.0.48:

Cruddle \Crud"dle\ (-d'l), v. i.
   To curdle. [Obs.]
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         See how thy blood cruddles at this.      --Bea? & FL.
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The Collaborative International Dictionary of English v.0.48:

Curdle \Cur"dle\ (k[^u]r"d'l), v. i. [From Curd.] [Sometimes
   written crudle and cruddle.]
   1. To change into curd; to coagulate; as, rennet causes milk
      to curdle. --Thomson.
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   2. To thicken; to congeal.
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            Then Mary could feel her heart's blood curdle cold.
                                                  --Southey.
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