The Collaborative International Dictionary of English v.0.48:

Iniquity \In*iq"ui*ty\, n.; pl. Iniquities. [OE. iniquitee, F.
   iniquit['e], L. iniquitas, inequality, unfairness, injustice.
   See Iniquous.]
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   1. Absence of, or deviation from, just dealing; lack of
      rectitude or uprightness; gross injustice;
      unrighteousness; wickedness; as, the iniquity of bribery;
      the iniquity of an unjust judge.
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            Till the world from his perfection fell
            Into all filth and foul iniquity.     --Spenser.
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   2. An iniquitous act or thing; a deed of injustice or
      unrighteousness; a sin; a crime. --Milton.
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            Your iniquities have separated between you and your
            God.                                  --Is. lix. 2.
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   3. A character or personification in the old English
      moralities, or moral dramas, having the name sometimes of
      one vice and sometimes of another. See Vice.
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            Acts old Iniquity, and in the fit
            Of miming gets the opinion of a wit.  --B. Jonson.
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