WordNet (r) 3.0 (2006):

uninhibited
    adj 1: not inhibited or restrained; "uninhibited exuberance"
           [ant: inhibited]

Moby Thesaurus II by Grady Ward, 1.0:

41 Moby Thesaurus words for "uninhibited":
   abandoned, go-go, immoderate, incontinent, indulgent, intemperate,
   irrepressible, lax, licentious, loose, nonrestrictive,
   out of control, out of hand, permissive, rampant, reinless,
   riotous, unbridled, unchecked, uncoerced, uncompelled,
   unconstrained, uncontrolled, uncurbed, unforced, ungoverned,
   unhampered, unmastered, unmeasured, unmuzzled, unreined,
   unrepressed, unreserved, unrestrained, unrestrictive, unruly,
   unsubdued, unsuppressed, untrammeled, wanton, wild