unobserved

from WordNet (r) 3.0 (2006)

unobserved
    adj 1: not observed [syn: {unobserved}, {unseen}]
    2: not observed; "managed to slip away unobserved"

from The Collaborative International Dictionary of English v.0.48

Unobserved \Unobserved\
   See {observed}.

from Moby Thesaurus II by Grady Ward, 1.0

38 Moby Thesaurus words for "unobserved":
      behind the curtain, behind the scenes, camouflaged, concealed,
      disguised, hidden, imperceptible, indiscernible, insensible,
      invisible, latent, out of sight, secret, sightless, submerged,
      unapparent, unbeheld, unbeholdable, unconsidered, undescried,
      undiscernible, unheeded, unmarked, unminded, unmissed, unnoted,
      unnoticed, unperceivable, unperceived, unrealized, unregarded,
      unremarked, unseeable, unseen, unthought-of, unviewed, unwitnessed,
      viewless