unperturbed

from WordNet (r) 3.0 (2006)

unperturbed
    adj 1: free from emotional agitation or nervous tension; "the
           waiters were unflurried and good natured"; "with
           contented mind and unruffled spirit"- Anthony Trollope
           [syn: {unflurried}, {unflustered}, {unperturbed},
           {unruffled}]

from The Collaborative International Dictionary of English v.0.48

Unperturbed \Unperturbed\
   See {perturbed}.

from Moby Thesaurus II by Grady Ward, 1.0

51 Moby Thesaurus words for "unperturbed":
      at rest, calm, cloistered, cool, dwindling, ebbing, even-tenored,
      halcyon, hushed, impassive, isolated, moldering, pacific,
      peaceable, peaceful, placid, quiescent, quiet, reposeful, reposing,
      restful, resting, secluded, sequestered, sequestrated, sheltered,
      smooth, still, still as death, stillish, stilly, stoic, stolid,
      subsiding, tranquil, unagitated, unbothered, undisturbed,
      unexcited, unflustered, unimpassioned, unmoved, unplagued,
      unruffled, unstirred, unstirring, untormented, untroubled, unvexed,
      unworried, waning