secretive

from WordNet (r) 3.0 (2006)

secretive
    adj 1: inclined to secrecy or reticence about divulging
           information; "although they knew her whereabouts her
           friends kept close about it" [syn: {close},
           {closelipped}, {closemouthed}, {secretive},
           {tightlipped}]

from The Collaborative International Dictionary of English v.0.48

Secretive \Se*cret"ive\, a.
   Tending to secrete, or to keep secret or private; as, a
   secretive disposition.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

37 Moby Thesaurus words for "secretive":
      close, closemouthed, dark, discreet, disinclined to communicate,
      evasive, excretory, lachrymal, lachrymose, lacrimatory,
      lactational, lacteal, lacteous, meaningless, mum, reserved,
      reticent, rheumy, salivant, salivary, salivous, secret,
      secretional, secretory, seminal, serous, shifty, sialagogic,
      silent, spermatic, taciturn, tight-lipped, uncommunicative,
      unconversable, unsociable, watering, watery

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