The Collaborative International Dictionary of English v.0.48:

Aslake \A*slake"\ ([.a]*sl[=a]k"), v. t. & i. [AS. [=a]slacian,
   slacian, to slacken. Cf. Slake.]
   To mitigate; to moderate; to appease; to abate; to diminish.
   [Archaic] --Chaucer.
   [1913 Webster]