untrustworthy

from WordNet (r) 3.0 (2006)

untrustworthy
    adj 1: not worthy of trust or belief; "an untrustworthy person"
           [syn: {untrustworthy}, {untrusty}] [ant: {trustworthy},
           {trusty}]

from The Collaborative International Dictionary of English v.0.48

Untrustworthy \Untrustworthy\
   See {trustworthy}.

from Moby Thesaurus II by Grady Ward, 1.0

42 Moby Thesaurus words for "untrustworthy":
      dangerous, desultory, doubtful, dubious, fly-by-night, hazardous,
      infirm, insecure, insubstantial, irresponsible, perilous,
      precarious, provisional, questionable, risky, rocky, shaky,
      shifting, shifty, slippery, temporary, tentative, ticklish,
      tottery, treacherous, trustless, unassured, uncertain,
      undependable, unfaithworthy, unhealthy, unpredictable, unreliable,
      unsafe, unsolid, unsound, unstable, unsteadfast, unsteady,
      unsubstantial, unsure, untrusty