The Collaborative International Dictionary of English v.0.48:

Cost \Cost\, n. [OF. cost, F. co[^u]t. See Cost, v. t. ]
   1. The amount paid, charged, or engaged to be paid, for
      anything bought or taken in barter; charge; expense;
      hence, whatever, as labor, self-denial, suffering, etc.,
      is requisite to secure benefit.
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            One day shall crown the alliance on 't so please
            you,
            Here at my house, and at my proper cost. --Shak.
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            At less cost of life than is often expended in a
            skirmish, [Charles V.] saved Europe from invasion.
                                                  --Prescott.
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   2. Loss of any kind; detriment; pain; suffering.
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            I know thy trains,
            Though dearly to my cost, thy gins and toils.
                                                  --Milton.
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   3. pl. (Law) Expenses incurred in litigation.
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   Note: Costs in actions or suits are either between attorney
         and client, being what are payable in every case to the
         attorney or counsel by his client whether he ultimately
         succeed or not, or between party and party, being those
         which the law gives, or the court in its discretion
         decrees, to the prevailing, against the losing, party.
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   Bill of costs. See under Bill.

   Cost free, without outlay or expense. "Her duties being to
      talk French, and her privileges to live cost free and to
      gather scraps of knowledge." --Thackeray.
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