The Collaborative International Dictionary of English v.0.48:

Furnish \Fur"nish\ (f[^u]r"n[i^]sh), v. t. [imp. & p. p.
   Furnished; p. pr. & vb. n. Furnishing.] [OF. furnir,
   fornir, to furnish, finish, F. fournir; akin to Pr. formir,
   furmir, fromir, to accomplish, satisfy, fr. OHG. frumjan to
   further, execute, do, akin to E. frame. See Frame, v. t.,
   and -ish.]
   1. To supply with anything necessary, useful, or appropriate;
      to provide; to equip; to fit out, or fit up; to adorn; as,
      to furnish a family with provisions; to furnish one with
      arms for defense; to furnish a Cable; to furnish the mind
      with ideas; to furnish one with knowledge or principles;
      to furnish an expedition or enterprise, a room or a house.
      [1913 Webster]

            That the man of God may be perfect, thoroughly
            furnished
            unto all good works.                  --2 Tim. iii.
                                                  17,
      [1913 Webster]

   2. To offer for use; to provide (something); to give
      (something); to afford; as, to furnish food to the hungry:
      to furnish arms for defense.
      [1913 Webster]

            Ye are they . . . that furnish the drink offering
            unto that number.                     --Is. lxv. 11.
      [1913 Webster]

            His writings and his life furnish abundant proofs
            that he was not a man of strong sense. --Macaulay.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

furnished \furnished\ adj.
   provided with necessary furnishings; -- used especially of
   rented apartments having furniture included in the rental
   price; as, a furnished apartment. Opposite of unfurnished.
   [Narrower terms: stocked, stocked with ; {appointed;
   well-appointed, well-found ; {fitted out, outfitted ]

   Syn: equipped.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

furnished
    adj 1: provided with whatever is necessary for a purpose (as
           furniture or equipment or authority); "a furnished
           apartment"; "a completely furnished toolbox" [syn:
           {furnished, equipped] [ant: unfurnished]