The Collaborative International Dictionary of English v.0.48:

Whether \Wheth"er\, pron. [OE. whether, AS. hw[ae]?er; akin to
   OS. hwe?ar, OFries. hweder, OHG. hwedar, wedar, G. weder,
   conj., neither, Icel. hv[=a]rr whether, Goth. hwa?ar, Lith.
   katras, L. uter, Gr. ?, ?, Skr. katara, from the
   interrogatively pronoun, in AS. hw[=a] who. ????. See Who,
   and cf. Either, Neither, Or, conj.]
   Which (of two); which one (of two); -- used interrogatively
   and relatively. [Archaic]
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         Now choose yourself whether that you liketh. --Chaucer.
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         One day in doubt I cast for to compare
         Whether in beauties' glory did exceed.   --Spenser.
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         Whether of them twain did the will of his father?
                                                  --Matt. xxi.
                                                  31.
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The Collaborative International Dictionary of English v.0.48:

Whether \Wheth"er\, conj.
   In case; if; -- used to introduce the first or two or more
   alternative clauses, the other or others being connected by
   or, or by or whether. When the second of two alternatives is
   the simple negative of the first it is sometimes only
   indicated by the particle not or no after the correlative,
   and sometimes it is omitted entirely as being distinctly
   implied in the whether of the first.
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         And now who knows
         But you, Lorenzo, whether I am yours?    --Shak.
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         You have said; but whether wisely or no, let the forest
         judge.                                   --Shak.
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         For whether we live, we live unto the Lord; and whether
         we die, we die unto the Lord; whether we live
         therefore, or die, we are the Lord's.    --Rom. xiv. 8.
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         But whether thus these things, or whether not;
         Whether the sun, predominant in heaven,
         Rise on the earth, or earth rise on the sun, . . .
         Solicit not thy thoughts with matters hid. --Milton.
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   Whether or no, in either case; in any case; as, I will go
      whether or no.

   Whether that, whether. --Shak.
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