A person who is not honest; often implies a character flaw rather than a single act.
He's a dishonest person, so I don't think he'll keep his promise.
You'd better watch out for that cheat.
Antonym: an honest person.
More common word for 'liar'; 不正直者 is broader, covering general dishonesty.
Compound of 不 (fu, 'not') + 正直 (shōjiki, 'honest') + 者 (mono, 'person').