air-slacked lime

Slack \Slack\, Slacken \Slack"en\, v. t.
   1. To render slack; to make less tense or firm; as, to slack
      a rope; to slacken a bandage. --Wycklif (Acts xxvii. 40)
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   2. To neglect; to be remiss in. [Obs.] --Shak.
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            Slack not the pressage.               --Dryden.
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   3. To deprive of cohesion by combining chemically with water;
      to slake; as, to slack lime.
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   4. To cause to become less eager; to repress; to make slow or
      less rapid; to retard; as, to slacken pursuit; to slacken
      industry. "Rancor for to slack." --Chaucer.
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            I should be grieved, young prince, to think my
            presence
            Unbent your thoughts, and slackened 'em to arms.
                                                  --Addison.
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            In this business of growing rich, poor men should
            slack their pace.                     --South.
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            With such delay
            Well plased, they slack their course. --Milton.
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   5. To cause to become less intense; to mitigate; to abate; to
      ease.
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            To respite, or deceive, or slack thy pain
            Of this ill mansion.                  --Milton.
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   {Air-slacked lime}, lime slacked by exposure to the air, in
      consequence of the absorption of carton dioxide and water,
      by which it is converted into carbonate of lime and
      hydrate of lime.
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