The Collaborative International Dictionary of English v.0.48:

Seclude \Se*clude\, v. t. [imp. & p. p. Secluded; p. pr. & vb.
   n. Secluding.] [L. secludere, seclusum; pref. se- aside +
   claudere to shut. See Close, v. t.]
   1. To shut up apart from others; to withdraw into, or place
      in, solitude; to separate from society or intercourse with
      others.
      [1913 Webster]

            Let Eastern tyrants from the light of heaven
            Seclude their bosom slaves.           --Thomson.
      [1913 Webster]

   2. To shut or keep out; to exclude. [Obs.] --Evelyn.
      [1913 Webster] -- Se*clud"ed*ly, adv. --
      Se*clud"ed*ness, n.
      [1913 Webster]

WordNet (r) 3.0 (2006):

seclude
    v 1: keep away from others; "He sequestered himself in his study
         to write a book" [syn: seclude, sequester,
         sequestrate, withdraw]

Moby Thesaurus II by Grady Ward, 1.0:

48 Moby Thesaurus words for "seclude":
   bolt, cloister, closet, confine, cop out, cordon, cordon off,
   cull out, divide, enclose, forsake the world, ghettoize, gin,
   go into retirement, immure, insulate, isolate, keep apart,
   keep aside, lay aside, live alone, live apart, live in retirement,
   pick out, put aside, quarantine, remain incommunicado, retire,
   riddle, rope off, rusticate, screen, seal off, segregate, separate,
   sequester, set apart, set aside, shut off, sieve, sift, sort out,
   stay at home, take the veil, thrash, thresh, winnow, withdraw