insolent

marked by casual disrespect; "a flip answer to serious question"; "the student was kept in for impudent behavior"

unrestrained by convention or propriety; "an audacious trick to pull"; "a barefaced hypocrite"; "the most bodacious display of tourism this side of Anaheim"- Los Angeles Times; "bald-faced lies"; "brazen arrogance"; "the modern world with its quick material successes and insolent belief in the boundless possibilities of progress"- Bertrand Russell