The Collaborative International Dictionary of English v.0.48:

Ween \Ween\, v. i. [OE. wenen, AS. w?nan, fr. w?n hope,
   expectation, opinion; akin to D. waan, OFries. w?n, OS. &
   OHG. w[=a]n, G. wahn delusion, Icel. v[=a]n hope,
   expectation, Goth. w?ns, and D. wanen to fancy, G.
   w[aum]hnen, Icel. v[=a]na to hope, Goth. w?njan, and perhaps
   to E. winsome, wish.]
   To think; to imagine; to fancy. [Obs. or Poetic] --Spenser.
   Milton.
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         I have lost more than thou wenest.       --Chaucer.
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         For well I ween,
         Never before in the bowers of light
         Had the form of an earthly fay been seen. --J. R.
                                                  Drake.
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         Though never a dream the roses sent
         Of science or love's compliment,
         I ween they smelt as sweet.              --Mrs.
                                                  Browning.
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