The Collaborative International Dictionary of English v.0.48:

Slake \Slake\, v. i.
   1. To go out; to become extinct. "His flame did slake." --Sir
      T. Browne.
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   2. To abate; to become less decided. [R.] --Shak.
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   3. To slacken; to become relaxed. "When the body's strongest
      sinews slake." [R.] --Sir J. Davies.
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   4. To become mixed with water, so that a true chemical
      combination takes place; as, the lime slakes.
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   Slake trough, a trough containing water in which a
      blacksmith cools a forging or tool.
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