1. Not worthy of trust or belief
   "an untrustworthy person";
   - untrusty

See also: devious, dishonest, dishonorable [US], dishonourable [Brit, Cdn], flakey [informal], flaky [informal], fly-by-night, shifty, slippery, tricky, undependable, unfaithful, unreliable

Antonym: trustworthy

Encyclopedia: Untrustworthy