impertinent
Meaning: rude, insolent
Usage: Most of your comments are so impertinent that I don’t wish to dignify them with an answer.
impudent
Meaning: casually rude, insolent, impertinent
Usage: The impudent young man looked the princess up and down and told her she was hot even though she hadn’t asked him.
insolent
Meaning: rude, arrogant, overbearing
Usage: That celebrity is so insolent, making fun of his fans right to their faces.
petulance
Meaning: rudeness, irritability
Usage: The Nanny resigned after she could no longer tolerate the child’s petulance.
pert
Meaning: flippant, bold
Usage: My parents forgave Sandra’s pert humor at the dinner table because it had been so long since they had last seen her.