The Collaborative International Dictionary of English v.0.48:

Boggle \Bog"gle\, v. i. [imp. & p. p. Boggled; p. pr. & vb. n.
   Boggling.] [ See Bogle, n.]
   1. To stop or hesitate as if suddenly frightened, or in
      doubt, or impeded by unforeseen difficulties; to take
      alarm; to exhibit hesitancy and indecision.
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            We start and boggle at every unusual appearance.
                                                  --Glanvill.
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            Boggling at nothing which serveth their purpose.
                                                  --Barrow.
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   2. To do anything awkwardly or unskillfully.
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   3. To play fast and loose; to dissemble. --Howell.
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   Syn: To doubt; hesitate; shrink; stickle; demur.
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