The Collaborative International Dictionary of English v.0.48:

Scruple \Scru"ple\, n. [L. scrupulus a small sharp or pointed
   stone, the twenty-fourth part of an ounce, a scruple,
   uneasiness, doubt, dim. of scrupus a rough or sharp stone,
   anxiety, uneasiness; perh. akin to Gr. ? the chippings of
   stone, ? a razor, Skr. kshura: cf. F. scrupule.]
   1. A weight of twenty grains; the third part of a dram.
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   2. Hence, a very small quantity; a particle.
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            I will not bate thee a scruple.       --Shak.
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   3. Hesitation as to action from the difficulty of determining
      what is right or expedient; unwillingness, doubt, or
      hesitation proceeding from motives of conscience.
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            He was made miserable by the conflict between his
            tastes and his scruples.              --Macaulay.
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   To make scruple, to hesitate from conscientious motives; to
      scruple.                                    --Locke.
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