The Collaborative International Dictionary of English v.0.48:

Inequality \In`e*qual"i*ty\, n.; pl. Inequalities. [L.
   inaequalitas.]
   [1913 Webster]
   1. The quality of being unequal; difference, or lack of
      equality, in any respect; lack of uniformity;
      disproportion; unevenness; disparity; diversity; as, an
      inequality in size, stature, numbers, power, distances,
      motions, rank, property, etc.
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            There is so great an inequality in the length of our
            legs and arms as makes it impossible for us to walk
            on all four.                          --Ray.
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            Notwithstanding which inequality of number, it was
            resolved in a council of war to fight the Dutch
            fleet.                                --Ludlow.
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            Sympathy is rarely strong where there is a great
            inequality of condition.              --Macaulay.
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   2. Unevenness; lack of levelness; the alternate rising and
      falling of a surface; as, the inequalities of the surface
      of the earth, or of a marble slab, etc.
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            The country is cut into so many hills and
            inequalities as renders it defensible. --Addison.
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   3. Variableness; changeableness; inconstancy; lack of
      smoothness or equability; deviation; unsteadiness, as of
      the weather, feelings, etc.
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            Inequality of air is ever an enemy to health.
                                                  --Bacon.
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   4. Disproportion to any office or purpose; inadequacy;
      competency; as, the inequality of terrestrial things to
      the wants of a rational soul. --South.
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   5. (Alg.) An expression consisting of two unequal quantities,
      with the sign of inequality (.gt. or .lt.) between them;
      as, the inequality 2 .lt. 3, or 4 .gt. 1.
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   6. (Astron.) An irregularity, or a deviation, in the motion
      of a planet or satellite from its uniform mean motion; the
      amount of such deviation.
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