The Collaborative International Dictionary of English v.0.48:

Yet \Yet\, conj.
   Nevertheless; notwithstanding; however.
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         Yet I say unto you, That even Solomon in all his glory
         was not arrayed like one of these.       --Matt. vi.
                                                  29.
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   Syn: See However.
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The Collaborative International Dictionary of English v.0.48:

Yet \Yet\, n. (Zool.)
   Any one of several species of large marine gastropods
   belonging to the genus Yetus, or Cymba; a boat shell.
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The Collaborative International Dictionary of English v.0.48:

Yet \Yet\, adv. [OE. yet, [yogh]et, [yogh]it, AS. git, gyt,
   giet, gieta; akin to OFries. ieta, eta, ita, MHG. iezuo,
   ieze, now, G. jetzo, jetzt.]
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   1. In addition; further; besides; over and above; still. "A
      little longer; yet a little longer." --Dryden.
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            This furnishes us with yet one more reason why our
            savior, lays such a particular stress acts of mercy.
                                                  --Atterbury.
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            The rapine is made yet blacker by the pretense of
            piety and justice.                    --L'Estrange.
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   2. At the same time; by continuance from a former state;
      still.
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            Facts they had heard while they were yet heathens.
                                                  --Addison.
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   3. Up to the present time; thus far; hitherto; until now; --
      and with the negative, not yet, not up to the present
      time; not as soon as now; as, Is it time to go? Not yet.
      See As yet, under As, conj.
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            Ne never yet no villainy ne said.     --Chaucer.
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   4. Before some future time; before the end; eventually; in
      time. "He 'll be hanged yet." --Shak.
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   5. Even; -- used emphatically.
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            Men may not too rashly believe the confessions of
            witches, nor yet the evidence against them. --Bacon.
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WordNet (r) 3.0 (2006):

yet
    adv 1: up to the present time; "I have yet to see the results";
           "details are yet to be worked out"
    2: 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]
    3: to a greater degree or extent; used with comparisons; "looked
       sick and felt even worse"; "an even (or still) more
       interesting problem"; "still another problem must be solved";
       "a yet sadder tale" [syn: even, yet, still]
    4: within an indefinite time or at an unspecified future time;
       "he longed for the flowers that were yet to show themselves";
       "sooner or later you will have to face the facts"; "in time
       they came to accept the harsh reality" [syn: yet, in
       time]
    5: used after a superlative; "this is the best so far"; "the
       largest drug bust yet" [syn: so far, yet]
    6: despite anything to the contrary (usually following a
       concession); "although I'm a little afraid, however I'd like
       to try it"; "while we disliked each other, nevertheless we
       agreed"; "he was a stern yet fair master"; "granted that it
       is dangerous, all the same I still want to go" [syn:
       however, nevertheless, withal, still, yet, all the
       same, even so, nonetheless, notwithstanding]

Moby Thesaurus II by Grady Ward, 1.0:

99 Moby Thesaurus words for "yet":
   above, additionally, after a while, after all, again, albeit,
   all included, all the same, along, already, also, although,
   altogether, among other things, and all, and also, and so, as well,
   as yet, at all events, at any rate, au reste, before, before all,
   beside, besides, beyond, but, by this time, earlier, early, else,
   en plus, ere, ere then, erenow, even, even so, eventually, except,
   extra, farther, finally, for all that, for lagniappe, formerly,
   further, furthermore, heretofore, hereunto, hitherto, howbeit,
   however, in addition, in any case, in any event, in due course,
   inter alia, into the bargain, item, just the same, likewise, more,
   moreover, nevertheless, nonetheless, notwithstanding, on the side,
   on top of, or ever, over, plus, previously, priorly, rather, save,
   similarly, so far, someday, sometime, somewhen, sooner or later,
   still, then, then as previously, theretofore, therewith, though,
   thus far, till now, to boot, to date, to this day, too, ultimately,
   until now, until this time, up to now, when