The Collaborative International Dictionary of English v.0.48:

Soothsay \Sooth"say`\, v. i. [Sooth + say; properly to say
   truth, tell the truth.]
   To foretell; to predict. "You can not soothsay." --Shak. "Old
   soothsaying Glaucus' spell." --Milton.
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The Collaborative International Dictionary of English v.0.48:

Soothsay \Sooth"say`\, n.
   1. A true saying; a proverb; a prophecy. [Obs.] --Spenser.
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   2. Omen; portent. Having
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            God turn the same to good soothsay.   --Spenser.
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