[1] : The Collaborative International Dictionary of English v.0.48

unruffled \unruf"fled\, a. pref. un- not + ruffled.
   not ruffled or agitated; smooth; calm; tranquil; quiet.
   1913 webster

         calm and unruffled as a summer's sea.    --addison.
   1913 webster unruinate

[2] : WordNet (r) 2.0

unruffled
     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
     2: free from disturbance; "a ribbon of sand between the angry
        sea and the placid bay"; "the quiet waters of a lagoon";
        "a lake of tranquil blue water reflecting a tranquil blue
        sky"; "a smooth channel crossing"; "scarcely a ripple on
        the still water"; "unruffled water" syn: placid, quiet,
         still, tranquil
see also:
unflurried unflustered unperturbed placid quiet still 
tranquil 

[3] : Moby Thesaurus II by Grady Ward, 1.0

109 moby thesaurus words for "unruffled":
   accordant, alike, at rest, automatic, balanced, calm, cloistered,
   collected, composed, consistent, consonant, constant, continuous,
   cool, correspondent, downy, dwindling, ebbing, equable, equal,
   even, even-tenored, flat, glabrate, glabrescent, glabrous, halcyon,
   homogeneous, hushed, immutable, impassive, imperturbable,
   invariable, isolated, leiotrichous, level, measured, mechanical,
   methodic, moldering, monolithic, nonchalant, of a piece, ordered,
   orderly, pacific, peaceable, peaceful, persistent, placid, plane,
   quiescent, quiet, regular, reposeful, reposing, restful, resting,
   robotlike, secluded, sequestered, sequestrated, sheltered, smooth,
   smooth-shaven, smooth-textured, stable, steadfast, steady, still,
   still as death, stillish, stilly, stoic, stolid, suave, subsiding,
   systematic, tranquil, unaffected, unagitated, unanimated, unbroken,
   unchangeable, unchanged, unchanging, undeviating, undifferentiated,
   undisturbed, undiversified, unexcited, unflappable, unflustered,
   uniform, unimpassioned, unimpressed, uninspired, unmoved,
   unperturbed, unrough, unroughened, unstirred, unstirring, unstruck,
   untouched, untroubled, unvaried, unvarying, waning

Unruffled >> U Words
Unruffled, definition of term: Unruffled
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