The Collaborative International Dictionary of English v.0.48:

Hence \Hence\ (h[e^]ns), adv. [OE. hennes, hens (the s is prop.
   a genitive ending; cf. -wards), also hen, henne, hennen,
   heonnen, heonene, AS. heonan, heonon, heona, hine; akin to
   OHG. hinn[=a]n, G. hinnen, OHG. hina, G. hin; all from the
   root of E. he. See He.]
   1. From this place; away. "Or that we hence wend." --Chaucer.
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            Arise, let us go hence.               --John xiv.
                                                  31.
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            I will send thee far hence unto the Gentiles. --Acts
                                                  xxii. 21.
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   2. From this time; in the future; as, a week hence. "Half an
      hour hence." --Shak.
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   3. From this reason; therefore; -- as an inference or
      deduction.
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            Hence, perhaps, it is, that Solomon calls the fear
            of the Lord the beginning of wisdom.  --Tillotson.
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   4. From this source or origin.
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            All other faces borrowed hence
            Their light and grace.                --Suckling.
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            Whence come wars and fightings among you? Come they
            not hence, even of your lusts?        --James. iv.
                                                  1.
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   Note: Hence is used, elliptically and imperatively, for go
         hence; depart hence; away; be gone. "Hence with your
         little ones." --Shak. -- From hence, though a pleonasm,
         is fully authorized by the usage of good writers.
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               An ancient author prophesied from hence.
                                                  --Dryden.
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               Expelled from hence into a world
               Of woe and sorrow.                 --Milton.
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The Collaborative International Dictionary of English v.0.48:

Hence \Hence\, v. t.
   To send away. [Obs.] --Sir P. Sidney.
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WordNet (r) 3.0 (2006):

hence
    adv 1: (used to introduce a logical conclusion) from that fact
           or reason or as a result; "therefore X must be true";
           "the eggs were fresh and hence satisfactory"; "we were
           young and thence optimistic"; "it is late and thus we
           must go"; "the witness is biased and so cannot be
           trusted" [syn: therefore, hence, thence, thus,
           so]
    2: from this place; "get thee hence!"
    3: from this time; "a year hence it will be forgotten"

Moby Thesaurus II by Grady Ward, 1.0:

37 Moby Thesaurus words for "hence":
   accordingly, as a result, away, because of that, because of this,
   consequently, ergo, for that, for that cause, for that reason,
   for this cause, for this reason, for which reason, forth, hereat,
   in the future, off, on that account, on that ground,
   on this account, out, propter hoc, so, then, thence, thereat,
   therefor, therefore, therefrom, thereof, thereupon, thus, thusly,
   thuswise, whence, wherefore, wherefrom