The Collaborative International Dictionary of English v.0.48:

Apart \A*part"\, adv. [F. [`a] part; (L. ad) + part part. See
   Part.]
   1. Separately, in regard to space or company; in a state of
      separation as to place; aside.
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            Others apart sat on a hill retired.   --Milton.
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            The Lord hath set apart him that is godly for
            himself.                              --Ps. iv. 3.
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   2. In a state of separation, of exclusion, or of distinction,
      as to purpose, use, or character, or as a matter of
      thought; separately; independently; as, consider the two
      propositions apart.
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   3. Aside; away. "Wherefore lay apart all filthiness and
      superfluity of naughtiness." --Jas. i. 21.
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            Let Pleasure go, put Care apart.      --Keble.
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   4. In two or more parts; asunder; to piece; as, to take a
      piece of machinery apart.
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WordNet (r) 3.0 (2006):

apart
    adv 1: separated or at a distance in place or position or time;
           "These towns are many miles apart"; "stood with his legs
           apart"; "born two years apart"
    2: not taken into account or excluded from consideration; "these
       problems apart, the country is doing well"; "all joking
       aside, I think you're crazy" [syn: apart, aside]
    3: away from another or others; "they grew apart over the
       years"; "kept apart from the group out of shyness"; "decided
       to live apart"
    4: placed or kept separate and distinct as for a purpose; "had a
       feeling of being set apart"; "quality sets it apart"; "a day
       set aside for relaxing" [syn: aside, apart]
    5: one from the other; "people can't tell the twins apart"
    6: into parts or pieces; "he took his father's watch apart";
       "split apart"; "torn asunder" [syn: apart, asunder]
    adj 1: remote and separate physically or socially; "existed over
           the centuries as a world apart"; "preserved because they
           inhabited a place apart"- W.H.Hudson; "tiny isolated
           villages remote from centers of civilization"; "an
           obscure village" [syn: apart(p), isolated, obscure]
    2: having characteristics not shared by others; "scientists felt
       they were a group apart"- Vannever Bush

Moby Thesaurus II by Grady Ward, 1.0:

134 Moby Thesaurus words for "apart":
   a huis clos, adrift, alien, alienated, all to pieces, alone, aloof,
   apart from, aside, aside from, asunder, at a distance, away,
   away from, behind closed doors, besides, bipartite, by itself,
   by two, companionless, detached, dichotomous, disconnected,
   discontinuous, discrete, disjunct, disrelated, dissociated, distal,
   distant, distinct, distinctly, divergent, except for, excepting,
   excluding, exotic, extraneous, far, far off, faraway, fifty-fifty,
   foreign, friendless, half-and-half, homeless, in a backwater,
   in camera, in chambers, in executive session, in half, in halves,
   in privacy, in private, in private conference, in privy,
   in the abstract, in the singular, in twain, in two, incoherent,
   incommensurable, incomparable, independent, independently,
   individually, insular, irrelative, isolate, isolated,
   januis clausis, kithless, lone, lonely, lonesome, long-distance,
   long-range, noncohesive, not counting, once, one by one, other,
   out-of-the-way, out-of-the-world, outlandish, particularly,
   partitioned, per se, piecemeal, privately, privily, quarantined,
   remote, removed, retired, rootless, secluded, segregate,
   segregated, separate, separated, separately, severally, shut off,
   single-handed, single-handedly, singly, singularly, sky-high,
   solitary, solo, strange, to one side, unabetted, unaccompanied,
   unaffiliated, unaided, unallied, unassisted, unassociated,
   unattached, unattended, unconnected, unescorted, unfrequented,
   unjoined, unrelatable, unrelated, unseconded, unsupported,
   unvisited, wide apart, wide away, withdrawn