The Collaborative International Dictionary of English v.0.48:

Leasing \Leas"ing\, n. [AS. le['a]sung, fr. le['a]s loose,
   false, deceitful. See -less, Loose, a.]
   The act of lying; falsehood; a lie or lies. [Archaic]
   --Spenser.
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         Thou shalt destroy them that speak leasing. --Ps. v. 6.
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         Blessed be the lips that such a leasing told.
                                                  --Fairfax.
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   Leasing making (Scots Law), the uttering of lies or libels
      upon the personal character of the sovereign, his court,
      or his family. --Bp. Burnet.
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