The Collaborative International Dictionary of English v.0.48:

Scruple \Scru"ple\, v. t.
   1. To regard with suspicion; to hesitate at; to question.
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            Others long before them . . . scrupled more the
            books of heretics than of gentiles.   --Milton.
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   2. To excite scruples in; to cause to scruple. [R.]
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            Letters which did still scruple many of them. --E.
                                                  Symmons.
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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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The Collaborative International Dictionary of English v.0.48:

Scruple \Scru"ple\, v. i. [imp. & p. p. Scrupled; p. pr. & vb.
   n. Scrupling.]
   To be reluctant or to hesitate, as regards an action, on
   account of considerations of conscience or expedience.
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         We are often over-precise, scrupling to say or do those
         things which lawfully we may.            --Fuller.
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         Men scruple at the lawfulness of a set form of divine
         worship.                                 --South.
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WordNet (r) 3.0 (2006):

scruple
    n 1: a unit of apothecary weight equal to 20 grains
    2: uneasiness about the fitness of an action [syn: scruple,
       qualm, misgiving]
    3: an ethical or moral principle that inhibits action
    v 1: hesitate on moral grounds; "The man scrupled to perjure
         himself"
    2: raise scruples; "He lied and did not even scruple about it"
    3: have doubts about