The Collaborative International Dictionary of English v.0.48:

as \as\ ([a^]z), adv. & conj. [OE. as, als, alse, also, al swa,
   AS. eal sw[=a], lit. all so; hence, quite so, quite as: cf.
   G. als as, than, also so, then. See Also.]
   1. Denoting equality or likeness in kind, degree, or manner;
      like; similar to; in the same manner with or in which; in
      accordance with; in proportion to; to the extent or degree
      in which or to which; equally; no less than; as, ye shall
      be as gods, knowing good and evil; you will reap as you
      sow; do as you are bidden.
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            His spiritual attendants adjured him, as he loved
            his soul, to emancipate his brethren. --Macaulay.
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   Note: As is often preceded by one of the antecedent or
         correlative words such, same, so, or as, in expressing
         an equality or comparison; as, give us such things as
         you please, and so long as you please, or as long as
         you please; he is not so brave as Cato; she is as
         amiable as she is handsome; come as quickly as
         possible. "Bees appear fortunately to prefer the same
         colors as we do." --Lubbock. As, in a preceding part of
         a sentence, has such or so to answer correlatively to
         it; as with the people, so with the priest.
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   2. In the idea, character, or condition of, -- limiting the
      view to certain attributes or relations; as, virtue
      considered as virtue; this actor will appear as Hamlet.
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            The beggar is greater as a man, than is the man
            merely as a king.                     --Dewey.
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   3. While; during or at the same time that; when; as, he
      trembled as he spoke.
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            As I return I will fetch off these justices. --Shak.
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   4. Because; since; it being the case that.
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            As the population of Scotland had been generally
            trained to arms . . . they were not indifferently
            prepared.                             --Sir W.
                                                  Scott.
      [1913 Webster] [See Synonym under Because.]
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   5. Expressing concession. (Often approaching though in
      meaning).
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            We wish, however, to avail ourselves of the
            interest, transient as it may be, which this work
            has excited.                          --Macaulay.
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   6. That, introducing or expressing a result or consequence,
      after the correlatives so and such. [Obs.]
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            I can place thee in such abject state, as help shall
            never find thee.                      --Rowe.
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   So as, so that. [Obs.]
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            The relations are so uncertain as they require a
            great deal of examination.            --Bacon.
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   7. As if; as though. [Obs. or Poetic]
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            He lies, as he his bliss did know.    --Waller.
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   8. For instance; by way of example; thus; -- used to
      introduce illustrative phrases, sentences, or citations.
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   9. Than. [Obs. & R.]
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            The king was not more forward to bestow favors on
            them as they free to deal affronts to others their
            superiors.                            --Fuller.
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   10. Expressing a wish. [Obs.] "As have,"

   Note: i. e., may he have. --Chaucer.
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   As . . as. See So . . as, under So.

   As far as, to the extent or degree. "As far as can be
      ascertained." --Macaulay.

   As far forth as, as far as. [Obs.] --Chaucer.

   As for, or As to, in regard to; with respect to.

   As good as, not less than; not falling short of.

   As good as one's word, faithful to a promise.

   As if, or As though, of the same kind, or in the same
      condition or manner, that it would be if.

   As it were (as if it were), a qualifying phrase used to
      apologize for or to relieve some expression which might be
      regarded as inappropriate or incongruous; in a manner.

   As now, just now. [Obs.] --Chaucer.

   As swythe, as quickly as possible. [Obs.] --Chaucer.

   As well, also; too; besides. --Addison.

   As well as, equally with, no less than. "I have
      understanding as well as you." --Job xii. 3.

   As yet, until now; up to or at the present time; still;
      now.
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WordNet (r) 3.0 (2006):

as yet
    adv 1: used in negative statement to describe a situation that
           has existed up to this point or up to the present time;
           "So far he hasn't called"; "the sun isn't up yet" [syn:
           so far, thus far, up to now, hitherto,
           heretofore, as yet, yet, til now, until now]