The Collaborative International Dictionary of English v.0.48:

Amphibolous \Am*phib"o*lous\, a. [L. amphibolus, Gr. ? thrown
   about, doubtful. See Amphibole.]
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   1. Ambiguous; doubtful. [Obs.]
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            Never was there such an amphibolous quarrel -- both
            parties declaring themselves for the king. --Howell.
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   2. (Logic) Capable of two meanings.
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            An amphibolous sentence is one that is capable of
            two meanings, not from the double sense of any of
            the words, but from its admitting of a double
            construction; e. g., "The duke yet lives that Henry
            shall depose."                        --Whately.
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